Normalise the scopes before you look at any totals
The first number you see anchors everything after it, so don’t look at totals yet. Take a sheet of paper and write down every trade any of the three bids mentions: demo, plumbing, electrical, HVAC, drywall, paint, flooring, tile, cabinets, fixtures, permits, dumpsters, supervision.
Now go bid by bid and put each line item under one of those headings. A line that says "kitchen — $18,400" gets split across cabinets, plumbing, electrical, and tile as best you can, or flagged as unsplittable. When you finish, every bid is described in the same vocabulary and the gaps become visible without you having to hunt for them.
Separate silence from exclusion
These are not the same thing, and the difference is worth money. An exclusion — "appliances by owner" — is the contractor telling you a boundary. You can price it and plan for it.
Silence is different. A bid that never mentions permits has not told you anything. Maybe they are included in the trade lines. Maybe the contractor is assuming you will pull them. Maybe they haven’t thought about it and will bring it up in week three, as a change order. Silence is the more expensive of the two, and it is the one that looks like a lower price on the page.
Price the gaps before you rank the totals
Once the scopes are lined up, every blank cell has a cost. Permits on a whole-house rehab run roughly $1,800–2,100 in many markets. Two 30-yard dumpsters and disposal run $1,200–1,800. Supervision, if it is billed separately, is often 8–12% of the job.
Add those numbers to the bid that omitted them. That is the comparison. It is common for the bid that arrived $12,000 cheaper to land within $2,000 of the others once the blanks are filled — and for the difference between the remaining two to be material grade, not labour.
Write the questions down before you call
Every gap and every difference between two bids is a question. Write all of them per contractor before you call anyone, because on the phone you will remember two.
Ask them the same way of each contractor. Different answers to an identical question tell you more about how a job will run than any line item does.
- Is this a fixed price or an estimate — and what moves it?
- What is not included that I will pay someone else for?
- Which lines are allowances rather than prices?
- Are permits inside this number, and are you pulling them?
- What is the payment schedule tied to?
Cheapest is not a recommendation
After all of that you may still pick the more expensive bid, and be right. A contractor who broke out supervision, priced permits, and named model numbers has told you they have thought the job through. That is worth a premium against someone who wrote one line and a number.
What you are buying with this exercise is not the cheapest price. It is knowing which price you are actually comparing.