Compare against the same written scope
Two bids for 'the same job' usually aren't comparing the same scope. Before bids go out, write the scope on one page — rooms, finish level, allowances, inclusions, exclusions. Bids returned against that page can actually be compared.
Written estimates: read the assumptions
A useful estimate names what is included, what is excluded, what allowances are used for unspecified items, and what assumptions the price depends on. Two estimates for 'the same job' diverge most often in the assumptions, not the line items.
- Inclusions and exclusions listed explicitly.
- Allowances called out where finishes are not yet specified.
- Assumptions about existing conditions.
- Payment schedule tied to milestones.
- Change-order process and pricing rules.
References and past work
References on similar projects are more useful than a long generic list. Ask about communication, schedule, change orders, cleanliness and how problems were handled — not just whether the client was 'happy.'
Licensing, registration and insurance
Licensing and insurance requirements vary by jurisdiction and trade. Verify status with the issuing authority, not only the contractor's website. Confirm general liability insurance and any required workers' compensation cover directly with the insurer.
Communication and red flags
Pre-contract communication is usually the best version of what working with the contractor will feel like during the project. Pressure to sign quickly, vague answers, reluctance to put things in writing or a missing license where the jurisdiction requires one are all signals worth taking seriously.
Why this matters
- Lowest-price comparisons tend to under-weight scope, schedule and risk.
- Verifying licenses and insurance directly with issuers reduces risk of working with an under-qualified contractor.
- Clarifying the change-order process up front avoids disputes mid-project.
What to check before deciding
- Bring a written one-page scope to every contractor conversation.
- Request written estimates with inclusions, exclusions, allowances and assumptions.
- Verify licensing and insurance with the issuing authority and the insurer.
- Contact references on similar projects in similar buildings.
- Confirm the change-order process and payment schedule in writing.
Common mistakes
- Comparing total bid prices without comparing assumptions.
- Skipping reference checks because the contractor seems friendly.
- Paying large up-front deposits with no milestone protection.
- Approving verbal change orders that get reconstructed later.
- Treating a one-page proposal as a contract.
When to involve a professional
- Local laws set contract, licensing, lien and consumer-protection rules. A qualified local lawyer can review larger contracts.
- Electrical, plumbing, gas and structural work should be executed by licensed trades and inspected as required.
- Where the contractor is responsible for design (design-build), verify the qualifications of the design team as well.
Sources and further reading
Where this answer draws context from
External links open the publishing organization directly. These sources provide background context — not project-specific rules. Always confirm specifics with the local building authority or qualified professionals.
U.S. Federal Trade Commission
FTC consumer advice
General consumer due-diligence and contract-handling guidance. Jurisdiction-specific rules apply outside the U.S.
consumer.ftc.gov(opens in a new tab)
Frequently asked questions
More questions readers ask about this topic
How many contractor bids should I get?
Three is a common starting point. The value of multiple bids depends on each being priced against the same written scope. One careful bid against a clear scope can beat three bids against a fuzzy one.
What is a fair deposit?
There is no universal answer, and some jurisdictions cap deposits by law. The principle is that payments should track work performed and materials delivered. Discuss the schedule of values before signing.
Should I always pick the highest-rated contractor online?
Online review scores are one signal among several. Direct references on similar projects, written estimates and verified licensing usually carry more weight than aggregate ratings.
What is a clear red flag during the bidding process?
Pressure to sign quickly, reluctance to provide a written scope or contract, missing license or insurance where the jurisdiction requires them, no usable references, or significant unexplained price gaps without an explanation.
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