How to Get and Compare Contractor Estimates

Getting multiple estimates is one of the smartest things you can do before hiring a contractor for a roofing, siding, window, or deck project. But not all estimates are created equal — and comparing them fairly requires knowing what to ask for and what to look for. Here’s how to get meaningful quotes and choose the right one.

Request at Least Three Estimates

Three is the minimum. It gives you a range to work with and helps you spot outliers — both unusually high bids that may include unnecessary work and unusually low bids that may cut corners. More than five estimates can become overwhelming and may slow down contractors who assume you’re just shopping price. Focus on three to five contractors who come recommended or have strong local reviews.

Provide the Same Information to Everyone

For a fair comparison, every contractor needs the same baseline: the same scope of work, the same materials (or equivalent options), and the same timeline. If one contractor is quoting a full tear-off and the other is quoting a second layer, you’re not comparing apples to apples. Write down your requirements before the first visit: square footage, material preferences, any specific concerns (e.g., ice dam history, ventilation issues), and your target completion date. Share this with each contractor so they’re bidding on the same project.

What a Good Estimate Includes

• Detailed scope of work — A clear description of what will be done, not vague phrases like “roof replacement” without specifics. For roofing: tear-off or overlay, number of layers, underlayment type, flashing, ventilation, cleanup.
• Materials specified — Brand, product line, color, and quantity. “Architectural shingles” is not enough — you want “GAF Timberline HDZ in Weathered Wood” or equivalent.
• Labor and timeline — Number of days, crew size, and what happens if weather delays the job.
• Warranties — Manufacturer warranty on materials and workmanship warranty from the contractor. Get the specifics in writing.
• Permits — Who pulls them, who pays for them, and whether the cost is included or separate.
• Payment schedule — Typical structure: deposit (often 10–30%), progress payments, and final payment upon completion. Avoid paying more than one-third upfront.
• Total price — A single, all-in number. Be wary of estimates that leave out disposal, permits, or “extras” that almost always come up.

How to Compare Estimates Fairly

Don’t default to the lowest bid. A bid that’s 20–30% below the others often means cheaper materials, less experienced labor, or hidden costs. Focus on:

Scope alignment — Do all three bids cover the same work? If one excludes disposal or permits, add those costs before comparing.

Material quality — Is everyone quoting the same tier of product? A lower bid that uses economy-grade materials may not be a better value over the life of the installation.

Reputation and references — The best price means nothing if the contractor doesn’t show up or does poor work. Our 10 questions to ask a contractor will help you vet each company beyond the number on the page.

Warranty — A slightly higher bid that includes a 10-year workmanship warranty may be a better deal than a lower bid with no workmanship coverage.

Red Flags in an Estimate

• Pressure to sign immediately or “lock in today’s price”
• No written estimate — only verbal numbers
• Request for full or majority payment upfront
• Vague or missing scope — “roof job” without specifics
• No license or insurance information
• Estimates that seem too good to be true — they usually are

Use Your Estimates to Negotiate (Carefully)

If you have a preferred contractor but their bid is higher, you can sometimes ask if they can match a competing bid — but only if the scope and materials are equivalent. Don’t expect a quality contractor to match a lowball bid; they may decline or explain why their price reflects better materials or labor. It’s reasonable to ask about flexibility on timing (off-season discounts) or payment terms. For a deeper look at typical costs in the region, see our guide on home exterior project costs in Northern Virginia.