An unfinished basement is 800–1,500 square feet of paid-for square footage your family isn’t using. Finishing it is one of the highest-leverage projects in any Eastern Idaho home. Here’s what it costs in 2026.
2026 cost ranges
Basic finish (open layout, no bath): $30–$55/sq ft
Mid-range with bath and bedroom: $55–$85/sq ft
Premium with wet bar, theater, full bath: $85–$130/sq ft
For a typical 1,000 sq ft Idaho Falls basement with one bedroom, full bath, and a family room: $60,000–$80,000 in 2026.
Egress window in every bedroom. Non-negotiable. 5.7 sq ft minimum clear opening, max 44″ sill height.
Smoke and CO detectors hardwired with battery backup.
Ceiling height of 7’0″ minimum in living areas (some jurisdictions allow 6’8″ beams).
GFCI protection in bathrooms and within 6 feet of any wet location.
Permitting required in Bonneville County for any framing, electrical, or plumbing.
Timeline
Permit to substantial completion for a typical Idaho Falls basement finish: 8–12 weeks. Add 3–4 weeks if you’re adding a bedroom that requires egress excavation.
The ROI question
Mid-range basement finishes in Idaho Falls typically recoup 70–75% of cost at resale. The bigger win is daily livability — you’re paying for square footage you couldn’t use before.
A 40×60 pole barn is the most common shop size we build in Eastern Idaho. Here’s exactly what it costs in 2026 and where the money goes.
The three price tiers
Shell only: $67,200–$100,800
Posts, trusses, metal siding and roofing, framed openings, no concrete, no doors, no electrical. $28–$42/sq ft. This is what you build when you’ll finish it yourself over time.
Insulated with slab and basics: $135,000–$168,000
Adds 6″ reinforced slab, R-25 wall insulation, R-49 ceiling, two 16×10 overhead doors, walk door, 200-amp electrical service, basic lighting. $55–$70/sq ft. Ready to work in.
Turnkey shop: $180,000–$240,000
Everything above plus radiant floor heat, finished interior (drywall and paint), upgraded lighting, 100-gallon air compressor wiring, hose reels, workbench plumbing, half-bath. $75–$100/sq ft. This is what working contractors build.
Where the money actually goes
Steel package and labor: $48,000–$72,000
Concrete slab (6″, reinforced): $22,000–$28,000
Site work and pad prep: $8,000–$15,000
Doors (two 16×10): $6,000–$9,000
Electrical (200-amp service + interior): $9,000–$14,000
Insulation: $11,000–$16,000
Permitting and engineering: $2,500–$5,000
Cost drivers most builders don’t mention
Sidewall height. Bumping from 12′ to 14′ adds $4K–$6K but matters every day you work in the shop.
Slab thickness. Going from 4″ to 6″ reinforced adds $4K but doubles the load capacity and saves you a tear-out down the road.
Roof pitch. 4/12 is cheapest. 6/12 or steeper sheds snow better and looks better but adds $3K–$5K to truss cost.
A lot of families around here already own their land. Maybe it’s been in the family, maybe you bought ten acres a few years back with this exact plan in mind. If you own a buildable lot in Idaho, you can build a custom home right on it. You don’t have to buy into anybody’s subdivision. Building on your own land puts you in control of where you sit, how big you go, and how it looks. It’s how most of our Eastern Idaho clients build. Here’s how it works, what it runs, and the steps to get there, whether you own the land free and clear or you’re about to buy it.
I’m Bryce Swager, founder of SwagerBuilds. We build on clients’ own lots all over Rigby, Idaho Falls, Rexburg, Jefferson County, and Teton Valley, everything from a tidy in town lot to raw acreage at the end of a dirt road.
Can I build a custom home on my own land in Idaho?
Yes. If you own a buildable lot, or you buy one, a custom builder can build on your land. The things that decide whether it’s buildable are zoning, legal access, utilities or well/septic feasibility, and any county or HOA requirements. Once the lot checks out, the build process is the same as any custom home: design, permits, site work, build.
What does “build on your own lot” actually mean?
Building on your own lot means you supply the land and a custom builder builds your home on it. You’re not buying a finished spec house and you’re not building inside a production builder’s development with three floor plans to choose from. You pick the plan, the finishes, and the builder. It’s the most flexible way to build, and across most of Eastern Idaho it’s just how things are done, because so many people already own ground.
Is your lot actually buildable? Five things to check
Before you fall in love with a floor plan, make sure the land can carry it. Here are the five things we look at on every lot.
Zoning and setbacks. Is it zoned residential, and how far does the house have to sit off the property lines, the road, and any water?
Legal access. A recorded, year round easement or real county road frontage. Not a two track across the neighbor’s field that everybody’s been using since 1985.
Water and waste. Either city water and sewer at the road, or enough room and the right soil for a well and septic. I covered the costs in Well and Septic Cost in Rural Idaho.
Ground and soil. Slope, drainage, rock, and the water table all change what your foundation costs.
Overlays and HOA rules. Floodplain, wildfire zones, and subdivision design review can all shape what you’re allowed to build.
Get a builder out to walk the lot before you commit. A bad lot can quietly add $40,000 to $100,000 to a build, or kill it outright. If you’re still shopping, have someone walk it with you before you close, not after.
What it costs to build on your own land in Idaho
Owning the land takes the biggest variable, the lot price, off the table. The build itself still runs $245 to $425 a square foot on the Eastern Idaho valley floor, and more up in Teton Valley. On raw land, set aside money for getting the site ready.
Well and septic. Usually $30,000 to $70,000 together on a rural lot.
Site work. Excavation, grading, the driveway, and utilities, generally 12 to 20 percent of the build cost.
Power and propane. Trenching for power and a tank if you’re not on natural gas.
Can I use my land as the down payment on a construction loan?
Often, yes. If you own the lot free and clear, lenders will frequently let that equity count toward your construction loan down payment. Check the specifics with your lender, but it’s one of the real perks of building on ground you already own.
Do you build on rural acreage, or just in subdivisions?
Rural acreage is most of what we do, because that’s most of Eastern Idaho. We’ll build on your land whether it’s a lot in town in Rigby or Idaho Falls or ten acres out in Jefferson County or Teton Valley. We just confirm the access, utilities, and well and septic first.
What if I haven’t bought the land yet?
Have a builder look at the lot before you close. We’ll flag the access, utility, soil, and septic issues that change the cost, so you buy a lot you can actually build on, at a price that pencils out.
Own a lot? Let’s see what it’ll hold
Send me your lot address or parcel number and a rough idea of what you want to build. We’ll do a free 30 minute review of the access, utilities, and well and septic, and put a realistic budget to building on your own land in Rigby, Idaho Falls, Rexburg, or Teton Valley.
I get the call almost weekly. A California investor — sometimes a family, sometimes a small real estate fund, sometimes a Bay Area tech operator with a side bet — has been running Teton Valley numbers in a spreadsheet, sees the gross revenue figures on AirDNA, and wants to know if those numbers actually pencil out for a build or remodel.
The short answer is: sometimes yes, sometimes no, and the spreadsheet you ran is almost certainly wrong in at least two places. I’m Bryce Swager. I build custom homes and remodel rentals in Teton Valley. This is the honest version of the ROI conversation.
The bigger picture: Teton Valley as an STR market
Teton Valley is one of the most desirable secondary-market vacation rental zones in the Mountain West — close enough to Jackson Hole to feel like the Tetons, cheaper than Jackson to buy into, serves both ski-season and summer demand, and growing in cultural cachet for Bay Area and Denver families. The market also has real constraints California investors routinely underestimate:
STR regulatory environment is different in Driggs vs. unincorporated Teton County vs. Victor. Different rules. Different licensing. Don’t assume.
ADR is highly seasonal — peak weeks (Christmas/New Year, Presidents Week, MLK, summer July weeks) carry the year. Shoulder seasons drag heavy.
Occupancy ceilings are lower than Joshua Tree or Park City — fewer year-round demand drivers.
Property management in a small market costs more in percentage terms than larger markets.
Construction cost per square foot is meaningfully higher than the comps you’ll see in lower-elevation Idaho.
STR regulations — the actual rules in Driggs, Victor, and unincorporated Teton County
This is the single most important section of this post. Don’t buy a property assuming you can short-term-rent it without checking. STR rules in Teton Valley have tightened in recent years and continue to evolve.
If you’re building from California: verify STR allowances on the specific parcel, in writing, before you close. Realtors are not the source of truth here. The municipality is.
City of Driggs. Driggs has an active short-term rental licensing and inspection program. STRs are typically permitted in certain zones with a license, life-safety inspection, and registration. City of Victor. Victor has its own STR ordinance and permitting process, with different rules from Driggs. Unincorporated Teton County. Teton County, Idaho regulates STRs separately. Some subdivisions also restrict STRs at the HOA / CC&R level — even if county rules allow them.
The pattern California investors get burned on most often: an HOA in an otherwise STR-permissive zone bans STRs in their CC&Rs, the realtor didn’t flag it, and the buyer closes without reading the CC&Rs. Always do all three checks: city/county ordinance, HOA CC&Rs, and any applicable zoning overlay. In writing. Before closing.
ADR, occupancy, and gross revenue — what the data actually shows
Metric
Realistic range
Notes
ADR (annual average)
$300–$550
AirDNA / Mashvisor Teton Valley
Peak-week ADR
$700–$1,500+
Holiday weeks, Presidents Week, prime summer
Shoulder ADR
$180–$320
April–May, October–early December
Annual occupancy
45%–62%
Top operators hit 65%+
Gross annual revenue
$80K–$220K
Wide range; depends on size, finish, location, ops
Top-decile gross
$250K–$400K+
Larger 4–6 bed, premium finish, hot-tub, view
Bedroom count matters. 4–6 bed homes outperform 2–3 bed dramatically per night and per year. Family-of-multiple-families demand is the highest-paying segment.
Hot tubs are nearly required. Listings without a hot tub underperform listings with one by a wide margin.
Garages matter for ski-season ADR. Heated garages and gear storage drive better reviews.
Real wood, real stone, real fireplace — the “ski-house” aesthetic — outperforms generic-mountain-modern in nightly rate.
View matters less than people think. Layout, sleeps-count, and amenity stack matter more than mountain view for ADR.
The remodel math: when an existing home pencils
If you’re buying an existing Teton Valley home to remodel and Airbnb, the math hinges on: (1) acquisition price vs. comparable un-remodeled comps, (2) remodel cost vs. ADR uplift it actually delivers, and (3) operating cost realism.
Scenario A: Dated 3-bed cabin, $725K, $200K remodel. Pre-remodel ADR ~$250 → post ~$400. Occupancy 50–55%. Gross ~$73K → ~$80K. Opex 35–45%. Net before debt service ~$45K–$52K. Cash-on-cash on the remodel: meaningful if you bought right.
Scenario B: 4-bed mid-finish, $1.4M, $350K remodel. Pre-remodel ADR ~$400 → post ~$625. Occupancy 55–62%. Gross ~$80K → ~$140K. Opex 35–45%. Net before debt service ~$80K–$90K.
Scenario C: 5–6 bed STR-optimized new build, $2.6M all-in. ADR $700–$900 weighted. Occupancy 55–62%. Gross $170K–$220K. Opex 35–45%. Net before debt service $100K–$140K. Harder to pencil without significant equity or partial use.
These are illustrative — the actual numbers depend on your specific property, your operations, and STR market conditions in the year you operate. Don’t lift these scenarios into a deal model without running your own underwriting.
Which remodels pay off — and which don’t
Pays back in ADR uplift:
Kitchen — major impact on listing photos and guest reviews.
Primary bath + at least one secondary bath — primary bath finish drives nightly rate.
Hot tub installation — among the highest-ROI single upgrades.
Heated garage or mudroom with ski/gear storage.
Real stone fireplace surround.
Bunk room conversions — turning a den into a bunk room adds 2–4 sleeps and meaningfully raises nightly rate.
Outdoor living: deck, fire pit, view-orientation.
Photography-first design choices.
Doesn’t pay back at the rate California buyers expect:
High-end appliances (guests notice if the dishwasher is loud, not the brand)
Wine fridges and bar built-ins in a property under 5 beds
Luxury primary closet build-outs
Heated driveways
Smart home complexity — guests often can’t operate it; service calls eat margin
Custom architectural features in places guests don’t photograph
The principle: spend where the listing photos and the guest reviews actually move. Anything that doesn’t show in a listing photo or trigger a 5-star review is owner-luxury, not STR investment.
The new build path: STR-optimized custom from the ground up
Bedroom count to 4–6. Maximize sleeps without crossing into “feels like a hostel.”
Bunk room + dedicated kids’ space that drives multi-family bookings.
Two living zones — one for adults, one for kids.
Heated garage with gear room, ski storage, boot dryers.
Hot tub with view orientation and privacy.
Mudroom directly off garage with bench seating, hooks, dog wash.
Outdoor living: covered deck, fire pit, fenced yard if dog-friendly.
Durable finishes — wide-plank floors that hide wear, hard countertops, paint that touches up easily.
Photography orientation — main living spaces oriented to the photogenic views.
A well-designed 5-bed STR-optimized new build in the $2.4M–$3.2M total range can land in the upper-decile gross revenue band — $200K+ annually — if operations and location are right.
Operating costs — what investors leave out of their spreadsheets
Line item
% of gross
Property management
18%–28%
Cleaning
10%–15%
Utilities (winter-heavy)
4%–8%
Internet, streaming, smart-home
1%–2%
Supplies, linens
2%–4%
Repairs + snow removal
4%–8%
STR-rated insurance
1%–3%
Hot tub, HVAC, septic
1%–2%
Total realistic opex
35%–50% of gross
If your spreadsheet has opex at 20% of gross, your spreadsheet is wrong. Fix it before you make an offer.
Self-manage vs. full-service property management
Self-managing from California is possible but punishing. The cleaners, the guest issues at midnight, the contractor coordination when something breaks, the snow-removal calls — they don’t respect Pacific time. Most California investors who self-manage burn out in 12–18 months and switch to local property management.
Full-service local property management runs 18%–28% of gross revenue, sometimes higher for boutique operators. The good ones earn their fee in higher occupancy, better reviews, and faster maintenance. Vet them like you’d vet a builder — references, response time, fee structure, transparency on their dynamic pricing.
Realistic ROI expectations
Cash-on-cash return on remodel investment: typically 8%–18%, sometimes higher
Cap rate on new-build STR (gross-to-acquisition): typically 5%–8%, occasionally higher
Total return including appreciation: historically strong in Teton Valley, but past appreciation is not a guarantee of future
Payback period on a remodel: typically 3–6 years on the remodel-specific spend
When Teton Valley STR doesn’t make sense for a California investor
You need this to cashflow in year one or two. STRs ramp. Plan for year 2–3 to hit stride.
You can’t tolerate seasonality. Mud season is real. April and May gross will disappoint you.
You’re not willing to verify STR rules before closing.
Your spreadsheet has opex below 30% of gross. It’s wrong; fix it.
You can’t afford to hold through a soft year.
For California investors comfortable with those realities, who buy right, build or remodel smart, and run real ops — Teton Valley is one of the better STR markets in the Mountain West.
Where to start
Lock the STR rule check. City, county, HOA. In writing. Before LOI.
Get a real underwrite. AirDNA gives directional. Local STR comps and a builder’s renovation estimate give actual.
Walk the property with a builder before close.
Decide self-manage vs. property-managed up front.
Vet the property manager as carefully as you vet the builder.
FAQ
What’s the realistic ROI on an Airbnb in Teton Valley?
Well-positioned, well-operated STRs in Teton Valley typically gross $80K–$220K annually, with operating costs of 35–50% of gross. Cash-on-cash returns on remodel investment commonly run 8–18%; new-build STRs typically run cap rates of 5–8% before appreciation.
Can I Airbnb a property in Driggs or Victor?
Sometimes — depends on the specific parcel, zone, city ordinance, and HOA. Driggs, Victor, and unincorporated Teton County each have separate STR rules, and many HOAs additionally restrict STRs in their CC&Rs. Always verify all three in writing before closing.
How much does it cost to remodel a Teton Valley home for Airbnb?
Typical remodels for STR optimization run $150K–$500K depending on scope. Kitchen + primary bath + hot tub + outdoor living + mudroom upgrades are the highest-ROI areas.
What ADR can I expect from a Teton Valley Airbnb?
Annual average ADR ranges from $300 to $550 for well-positioned, well-managed properties. Peak weeks command $700–$1,500+. Shoulder seasons drag heavy.
How much do property managers charge in Teton Valley?
Full-service local property management typically runs 18%–28% of gross revenue. Self-management is possible but operationally heavy when you’re in California.
What’s the biggest mistake California investors make on Teton Valley STRs?
Three tied for first: (1) not verifying STR rules at the parcel level before closing, (2) undercounting operating costs in their spreadsheet, and (3) overspending on owner-luxury features that don’t move ADR or reviews.
Should I build new or remodel for an Airbnb in Teton Valley?
Depends on price-to-build vs. price-to-buy in your target zone, and on whether existing properties let you deliver the bedroom count and amenity stack the market wants. Smaller 3-bed remodels often pencil better; large 5–6 bed STR programs often have to be new builds.
Author: Bryce Swager — owner-builder at SwagerBuilds. Building and remodeling STRs in Teton Valley for California-based investors since 2020.
Building a custom home looks like chaos from the outside. It isn’t. Every good build moves through nine stages in the same order: set your budget, lock down land, line up financing, pick your builder, design the home, get through permits and engineering, prep the site, build, and close out. Rush one of the early stages and you’ll pay for it later in delays and change orders. This is the same checklist I walk every SwagerBuilds client through, so use it to keep your own build on the rails from day one.
I’m Bryce Swager. I’ve been building custom homes across Eastern Idaho since 2016, in Rigby, Idaho Falls, Rexburg, and up in Teton Valley. The order below is exactly how our cleanest projects run.
What are the first steps to building a custom home in Idaho?
Start with your budget and your financing before you fall for a floor plan or a lot. Then lock down land, bring a builder in early while you’re still designing, and freeze the design before you break ground. Almost every expensive mistake I see traces back to someone skipping straight to drawings without settling the budget first.
The nine stages, with real timelines
Here’s the whole sequence with a realistic window for each stage on a typical Eastern Idaho build.
Stage
Typical timeline
1. Set your budget
1 to 2 weeks
2. Lock down land
2 to 8 weeks
3. Line up financing
2 to 4 weeks (overlaps)
4. Pick your builder
30 to 60 days
5. Design the home
2 to 4 months
6. Permits and engineering
1 to 2 months
7. Site prep
3 to 6 weeks
8. Construction
8 to 12 months
9. Closeout and move in
2 to 4 weeks
All told, most Eastern Idaho custom homes run 14 to 18 months from your first phone call to keys in your hand. I broke the build schedule down month by month in How Long Does It Take to Build a Custom Home in Idaho.
Stage 1: Set your budget first
Before anything else, decide your all in number. Home, land, site work, and a 10 to 15 percent cushion. Knowing that number keeps you from designing a house you can’t actually build. On the Eastern Idaho valley floor, plan on $245 to $425 a square foot for the build itself. I keep the current numbers updated in Cost to Build a House in Idaho.
Stage 2: Lock down your land
Buy the lot, or make sure the one you already own will actually work. Check the zoning, the access, the utilities, whether you can get a well and septic in, and any HOA or county overlays. A beautiful plan on a bad lot is just an expensive headache. Already own your land? I wrote a whole guide on it: Build on Your Own Lot in Idaho.
Stage 3: Line up financing
Most custom homes run on a construction loan that rolls into a mortgage when the house is done. Get pre qualified early, because your loan amount is your real budget ceiling, and lenders want to see that you have a builder and a plan. Don’t forget to budget for the loan interest you’ll carry during the build.
Stage 4: Pick your builder
Bring your builder in while you’re still designing, not after the plans are done. A good one keeps the design inside your budget instead of redrawing it later. Check the license and insurance, walk through some finished homes, call a couple of past clients, and make sure the contract is a fixed price. I put the full vetting list here: How to Choose a Custom Home Builder in Eastern Idaho.
Stage 5: Design the home
This is where you go from rough sketches to schematic design to real construction drawings. Lock your layout, your kitchen, your primary suite, and your exterior before you break ground. Changing your mind mid build is the single most common reason a project blows its schedule and its budget.
Stage 6: Permits and engineering
Structural engineering, septic design, and county permit submission all happen here. In Eastern Idaho that means dealing with Bonneville, Jefferson, Madison, or Teton County, and they each run on their own clock. The day permits go in, order your long lead items like windows and custom cabinets so they’re not the thing holding you up later.
Stage 7: Site prep
Excavation, grading, the driveway, utilities, the well, the septic. On a rural lot this is a real line item, often 12 to 20 percent of the build cost. Get it right and everything after it sits on solid ground. Literally.
Stage 8: Construction
Foundation, framing, dry in, mechanicals, insulation, drywall, then all the finishes. This is where being able to see your job pays off. We run every build on JobTread, so you get daily photos and a live budget instead of sitting at home wondering what happened on site today.
Stage 9: Closeout and move in
Final inspections, the punch list, your certificate of occupancy, and the walkthrough. A builder who stands behind the work backs it in writing. We carry a structural warranty that runs ten years. Then you get your keys and it’s home.
Common questions about building in Idaho
What’s the very first step to building a house in Idaho?
Setting your all in budget. Before land, before plans, before a builder, you need your number. It decides what size and finish level you can realistically build, and it keeps the whole project honest.
Do I buy land or pick a builder first?
Do them side by side if you can. Have a builder look at a lot before you close on it. We catch access, utility, well, and septic problems that can add tens of thousands to a build. A bad lot can sink a good budget before you ever start.
When do I lock the design?
Before you break ground. Every layout change, every new kitchen idea, every swapped selection after construction starts costs you time and money. A disciplined builder won’t pour a foundation under a design that’s still moving.
Ready to start your build?
If you’re early in the process anywhere in Rigby, Idaho Falls, Rexburg, or Teton Valley, we’ll help you get the first steps right. Book a free 30 minute call and we’ll map out your budget, your land, and your timeline before you spend a dollar.
