Hiring guide

How to get 3 comparable bids

"Get three bids" is the most common home services advice and the most commonly butchered. Three random bids on three different versions of the same project are worse than one well-defined bid. Three comparable bids on the same defined scope tell you the market price within 15%. Here's the actual process.

Why three (not two, not five)

Two bids only tell you which one is cheaper. They don't tell you whether the cheaper one is reasonable or whether the more expensive one is gouging. With two bids and a 40% spread, you have no way to know which is the outlier.

Three bids form a triangle. Two will cluster within 15–25% of each other; the third will either confirm that range (legitimate price) or stand alone as an outlier (lowball or premium). Three is the minimum for a real market read.

Five bids is mostly overkill. By the time you've interviewed five contractors, you've spent 20+ hours of due diligence and your top three contractors are getting tired of waiting. Five only makes sense for major projects ($50,000+) where the cost of choosing wrong is high enough to justify the extra hours.

The scope sheet — write it BEFORE calling contractors

The single biggest mistake homeowners make is letting each contractor define the scope themselves. They walk through, take measurements, and bid on whatever they think the job is. You end up with three bids on three different projects.

Instead: write a one-page scope sheet before you make the first call. Hand the same sheet to every bidder. They'll bid on the same defined work, and the bids become comparable.

A good scope sheet has six sections:

What you want done (in plain language). Three sentences. "Replace the asphalt roof on the main house. 2,200 square feet of roof area, 6/12 pitch, two stories. Existing decking to be inspected and patched as needed."
What's specifically included. "Tear-off of existing layer. New ice-and-water shield at eaves and valleys. New 30-lb felt underlayment. New architectural asphalt shingles, 30-year warranty class. New flashing at chimneys and skylights. New ridge vents."
What's specifically excluded. "Gutter replacement, attic insulation, chimney repair. These will be quoted separately if needed."
Material preferences (if any). "Prefer GAF or Owens Corning architectural shingles. Color: Driftwood Gray or similar."
Timeline. "Ready to start within 30 days of contract signing. Prefer completion within 2 weeks of start."
How you want the bid structured. "Please provide an itemized fixed-price bid showing materials, labor, permits, disposal, and any allowances separately."

Email this scope sheet to each contractor before they visit. The visit becomes about confirming details and asking site-specific questions — not redefining the project on the fly.

How to source the three bidders

Where you get the bidders matters as much as the bids themselves. The healthiest mix:

One referral from someone you trust. A neighbor who had similar work done, a local realtor or home inspector, a friend with relevant industry experience. Referrals filter for contractor reliability better than any review platform.
One from a verified local source. Your state contractor licensing board's online directory often has searchable lists. Angi or HomeAdvisor work — but treat them as a starting point for vetting, not a recommendation.
One from the local trade association. Many trades have state-level associations (e.g., state Roofing Contractors Association, state HVAC Contractors Association). Member directories are smaller but tend to skew toward established businesses that have been around longer.

Avoid: door-to-door pitches (especially after a storm), Facebook marketplace, Craigslist for any project over $1,000. The savings rarely cover the risk.

The bid visit script

Every contractor should get the same 30–45 minute bid visit. Walk the project with them. Hand them the scope sheet. Then ask the same five questions of each:

"Anything in this scope you'd handle differently than I've described?" — surfaces contractor-specific recommendations and lets them flag if they think the scope is wrong.
"What's the typical price range for a project like this in this area?" — without committing them to their bid number, gets their read of the market.
"If we hit unexpected conditions, what's the change-order process?" — surfaces their change-order policy verbally before it shows up in the contract.
"How busy are you? Realistically when could you start?" — schedule realism. Contractors who say "next week" while clearly busy are either lying or about to short-staff your project.
"Can you send me your COI and license number tomorrow?" — sets the credentials-verification clock.

Don't talk price during the visit. Don't share what other contractors quoted. Don't share your budget. All of those bias the bid in ways that benefit the contractor, not you.

Verify credentials before you compare numbers

A bid from an unlicensed or uninsured contractor isn't a data point. It's noise, and it drags your whole comparison down because it's usually the lowest number on the table. Before the bids land, run three checks on each bidder.

License. Look up the license number on your state board's website and confirm it's active, in the right classification for the work, and free of recent disciplinary action. Takes five minutes per contractor.

Insurance. Ask for the certificate of insurance to be sent directly from the contractor's insurance agent, not forwarded as a PDF — forwarded certificates are easy to fake or let lapse. It should show general liability (at least $1 million is standard) and workers' compensation. A contractor without workers' comp puts an injured worker's claim on your homeowner's policy.

References. Call two, and ask one question that matters: "Would you hire them again for a bigger job?" The pause before the answer tells you more than the answer itself.

Any bidder who fails a check comes out of the pool, even with a great number. Replace them and keep the count at three. This is also why the lowest bid deserves the hardest scrutiny: cutting insurance and licensing costs is one of the few ways to legitimately undercut the market by 30%, and you're the one carrying that risk.

Normalize for materials and start date

Two bids that look $3,000 apart can be identical once you adjust for materials grade. A 30-year architectural shingle and a 50-year designer shingle differ by $1,500–$3,000 on a typical roof; a 14 SEER and an 18 SEER condenser differ by more. Before comparing totals, lay the spec sheets side by side and ask any bidder who quoted a different product line to re-price with the one named in your scope sheet. Most will, same day.

Timing works the same way. A contractor who can start next week is often pricing to fill a schedule gap and may come in 10–15% under one booked out three months. That discount can be real money. Just ask why the calendar is open: a slow season is a fine answer, a string of cancellations is not.

The mid-bid is usually the winner

When three legitimate contractors bid on the same well-defined scope, the bids almost always pattern this way:

The high bid is from an established contractor with good reputation, longer warranty, premium materials, and more cushion for unexpected work.
The low bid is from a newer contractor, undercapitalized contractor, or one cutting corners on materials or labor.
The mid-bid is the market price for the work as defined.

The mid-bid wins most of the time because it represents what the project actually costs to do correctly. The high-bid contractor isn't gouging — they're charging for the reputation and warranty premium. The low-bid contractor isn't being generous — they're either missing scope or planning to make up margin through change orders.

Exception: if the high-bidder is a specialist whose work quality justifies the premium and the project is high-stakes (foundation, structural, complex roof), the high bid is sometimes the right choice. Otherwise, mid.

What to do when bids are 50%+ apart

If your three bids are spread more than 50% from low to high, something is wrong. Almost always one of these three things:

1. The scope wasn't well-defined. Each contractor priced a different version of the project. Fix: walk the project with each, refine the scope sheet, and re-bid. Often the spread closes to under 20% on the second round.

2. The low bidder is missing material costs, not just labor. Walk through the materials list with each bidder. Often the low bid uses lower-grade shingles, thinner gauge metal, or no underlayment at all.

3. The market is genuinely fragmented. In some metros, established contractors charge 1.5–2× what newer ones do for legitimate reasons (insurance, warranty backing, employee benefits) but the work is comparable. Walk one of the references for the low bidder; if the work quality is real, the low bid might be a deal.

Re-bidding after the first round

If the first round of bids isn't clean, don't shrug and pick. Re-bid. Real contractors expect this for projects over $10,000. The conversation:

"Thanks for your bid. After comparing all three, I want to make sure we're pricing the same scope. I'm sending an updated scope sheet — please re-confirm your bid against this revised version. I'll have a decision within 7 days of receiving the revised bids."

This filters for two things: contractors who take the project seriously enough to re-engage (good sign), and contractors who push back on re-bidding because their original bid was loose (bad sign — and useful information).

When to skip the three-bid process

Three bids isn't always worth the time. Skip and go to a single trusted contractor when:

The project is under $2,000. Vetting time exceeds price-discovery value.
It's an emergency repair (active leak, no heat in January). Get one trusted contractor on-site fast; price-shop after the leak is stopped.
You have a long-standing relationship with a contractor who has done good work and prices fairly. Two bids from new contractors won't tell you anything you don't already know.
The work is highly specialized and only 1–2 contractors in your area do it. Multiple bids on a niche specialty often surface contractors who don't actually do that work but will subcontract it.

Document everything in writing

Whatever bid you accept, the win condition is the same: the work matches the scope sheet, the price matches the bid, change orders are in writing before work proceeds, and the warranty is documented and transferable. The contractor selection process is the cheap part of the project. The execution discipline is what protects the spend.

Always verify the scope, the bid, and the warranty terms with a licensed local contractor and your state's contractor licensing board before signing.

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