Why Three Custom Home Bids Don’t Compare (And How to Level Them)

Everyone tells you to get three bids. Nobody tells you that the three numbers you get back are not describing the same house — which makes comparing them roughly as useful as comparing three grocery receipts without knowing what’s in the bags.

I’ve been building for 20 years and I’ve lost jobs to bids I knew would finish higher than mine. Sometimes the client called me 14 months later to say so. Here’s how to avoid being that client.

The spread is almost never about profit margin

When three bids come back 15–25% apart, the instinct is to assume the high builder is greedy. Occasionally true. Usually not.

In this market, we’re all buying lumber from the same yards, hiring from the same pool of framers and tile setters, and pulling permits from the same counties. Nobody has a secret 20% material discount. If the numbers are far apart, the scopes are far apart.

Four things create almost all of the spread:

1. Allowances. A dollar placeholder for something nobody has priced yet. Set them low and your bid looks great. Here’s how allowances actually work.
2. Exclusions. Site work, well and septic, driveway, retaining, landscape, utility trenching, engineering. Any one of them is five or six figures on a mountain lot.
3. Contract type. A cost-plus “estimate” and a fixed price are different species of number. One is a commitment. One is a forecast.
4. Drawing completeness. Nobody can price a house that isn’t fully drawn. Builders bidding off schematic drawings are guessing, and the guess is always optimistic.

What that looks like in numbers

Illustrative example, not a quote. Same 2,500 SF house, same Driggs lot, three builders.

Bid	Structure	Number on paper	Where it actually finishes
Builder A	Fixed price, heavy allowances, site work excluded	$875,000	~$1,180,000
Builder B	Cost-plus, 15% fee on an estimate	$940,000 est.	~$1,145,000
Builder C	Fixed after design lock, zero allowances, site work included	$1,050,000	$1,050,000

Builder A wins the job by $175,000 and finishes $130,000 above the builder who looked expensive. Builder B’s fee grew with the budget — that’s not misconduct, it’s how cost-plus is built. Builder C never moved because there was nothing left to discover.

That gap isn’t hypothetical. Custom builds routinely land 20–40% over their contract number, and it’s nearly always scope that was never nailed down. More on cost-plus vs fixed-price.

Level the bids before you compare them

“Leveling” is what commercial owners do as a matter of course and residential clients almost never do. You rewrite all three bids into the same format so you’re comparing the same house. Build one sheet with these rows and fill a column per builder:

• Site work — excavation, fill, grading, driveway, retaining
• Well, septic, and utility trenching (real numbers here)
• Foundation type and insulation package
• Framing package and floor system
• Window and door manufacturer and line — by name, not “quality windows”
• Roofing material and gauge
• Exterior cladding and water-resistive barrier
• HVAC type and whether radiant is included
• Cabinet allowance or actual cabinet quote
• Countertop, tile, plumbing fixture, lighting, appliance, and flooring dollars
• Interior doors, trim package, and paint
• Engineering, permits, and impact fees (by county)
• Landscape, irrigation, and final grade
• Builder fee or overhead and profit — stated as a number
• Contingency, and who controls it

Every blank cell is a future change order. When you fill the blanks at market rate, the three bids usually land within a few percent of each other — and the ranking flips.

Give all three builders the same package

You cannot level bids that came from different information. Before you ask anyone for a number, hand every builder the identical packet:

• Complete drawings — not schematics. Plans, elevations, sections, and a structural set.
• A written finish specification. Actual manufacturers and model numbers, not adjectives.
• Your survey, soils report, and any subdivision or HOA design requirements.
• A written statement of what you expect included: site work, utilities, landscape, appliances.
• The same deadline and the same format request.

Here’s the catch most owners hit: producing that packet is the design phase, and it costs money. Which is exactly why I sell design as its own agreement before I’ll price a build. Nobody can hand you a number they’ll stand behind on a house that hasn’t been drawn. A builder who gives you a firm price off a napkin sketch is telling you something about how the rest of the job will go. How the design agreement works.

What has to be in the construction contract

Once you’ve picked a builder, the bid becomes a contract — and this is where the protection actually lives. Read for these:

• Scope of work, incorporated by reference. The drawings and the finish spec named by date and revision number, attached as exhibits. If the spec isn’t attached, there is no scope.
• The price, and what makes it move. Fixed, cost-plus, or fixed-with-allowances — stated plainly, with every trigger for a price change listed.
• Allowance schedule. If there are allowances, every one itemized with its dollar figure. Mine is a short list because the selections are made before signing.
• Change order procedure. Written, priced, and signed before the work happens. Verbal approvals disallowed in writing. What good change orders look like.
• Draw schedule tied to completed work, not to the calendar. How draws work on an Idaho construction loan.
• Lien waivers with every draw. Conditional on progress payments, unconditional on final. This is what stops a sub who wasn’t paid from attaching your title. Mechanic’s liens in Idaho.
• Schedule, with substantial completion defined and weather and change-order delays handled explicitly.
• Insurance and license. General liability and builder’s risk limits, workers’ comp, and who carries which.
• Warranty terms and the punch list process. What a builder warranty covers in Idaho.
• Dispute resolution and termination. How disagreements get settled, what triggers termination on either side, and how the job gets valued and closed out if it happens.

Have a real estate or construction attorney read it. If you’re already an attorney, read the termination and lien-waiver clauses first — that’s where the asymmetry usually hides.

How many bids, and how to run it

Three is right. Two gives you no pattern. Five wastes weeks and gets you ignored — good builders in a small valley know when they’re one of five, and they’ll price high or pass.

1. Vet before you bid. Licensing, insurance, lien history, finished projects at your size, and reference calls. Use these 10 questions. A number from a builder you wouldn’t hire is noise.
2. Tell them they’re one of three. Serious builders respect it. It also tells you who negotiates against a competitor and who explains their own process.
3. Give the identical packet and the same deadline.
4. Level the bids. Fill the blanks at market rate.
5. Bring your questions back to each builder individually. Their answers matter more than the original number.

Four questions that expose a lowball

1. Is this fixed or an estimate — and if fixed, fixed as of what?
2. What is excluded from this number entirely?
3. List every allowance and the dollar figure behind it.
4. On your last three finished homes, what was the final price versus the original contract?

Question four sorts the field faster than anything else on this page. A builder who tracks it answers in ten seconds. A builder who doesn’t will tell you every job is different.

Red flags while you’re collecting bids

• A bid that arrives in two days. Nobody priced your house. They applied a square-foot rate and called it a bid.
• A number with no scope document behind it. A price on letterhead is not a bid.
• Pressure to sign before the drawings are done.
• A large deposit before mobilization. Deposits that fund the previous client’s job are how builds stall. Ask how they’re capitalized and whether they have the crew for your job.
• Refusing to name their subs. In a valley this small, you can call them.
• Undercutting a competitor’s number on the spot. If they can drop $40,000 in a phone call, the number was never real.

The short version

Get three bids. Just don’t compare them as written. Level them onto one sheet, fill every blank at market rate, and pick from the leveled numbers — then read the contract like the scope depends on it, because it does.

Related: is a premium custom home builder worth it?

Frequently asked questions

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Bring me the other two bids

Book a 15-minute planning call and bring what you’ve got. I’ll tell you what’s missing from each one — including when the honest answer is that another builder is the better fit for your project.

— Bryce Swager, owner and lead builder, SwagerBuilds. Rigby, Idaho. Custom homes across Teton Valley, Eastern Idaho, and Jackson Hole.