How to compare exterior remodeling estimates
Two estimates for the same job are thousands apart. How do I tell what I'm actually comparing?
Compare the scope line by line before you compare the totals. A lower number often leaves out preparation, hidden-damage handling, or finish work that the other estimate includes. Line up what each one says about the work included, the materials named, preparation and cleanup, exclusions, and how changes are handled. If any of those is missing, ask for it in writing before deciding.
Start with the scope, not the total
Exterior work is priced by what is done, and two contractors rarely describe the same job the same way. One estimate may replace all the trim; another may reuse it. One may include priming bare wood; another may assume the paint covers it. Neither is wrong on its face, but they are different jobs.
Read each estimate and write the tasks in a simple list. Then check what one includes that the other does not. The gaps are usually in preparation, hidden-damage handling, and finish work, and they are usually where the price difference lives.
Five things every complete estimate makes clear
- The work included: each task, by wall, opening, or roof section.
- The materials proposed: product type, profile or grade, and finish, specific enough to look up.
- The preparation and cleanup: what is protected, what is removed, and what the site looks like at the end of each day.
- Any exclusions: what is not in the price, such as painting, permits, or interior finish.
- How changes are handled: what happens when hidden damage appears or you change a selection, and how that is priced.
A worked example: two siding estimates, $6,000 apart
Here is the shape of a comparison that comes up constantly on 1970s and 1980s wood-sided homes in the Sacramento area. Both estimates are for replacing the siding on the same 1,600-square-foot single-story house. The numbers are illustrative, not quotes; the point is the lines, not the totals.
| Line | Estimate A (lower) | Estimate B (higher) |
|---|---|---|
| Siding material | "Fiber cement lap siding" | Fiber cement lap, 8.25-inch smooth, primed; brand and profile named |
| Water-resistive barrier | Not mentioned | New barrier over all walls, taped seams |
| Window and door flashing | Not mentioned | New head flashing and sill pan at every opening (14 openings listed) |
| Trim and corners | "Reuse existing trim" | New corner boards and window trim, primed fiber cement, sizes listed |
| Sheathing damage | Not mentioned | $X per 4×8 sheet, approved before installation |
| Paint | "Paint included" | Two coats acrylic on body and trim; colors approved by sample; caulk all joints |
| Cleanup and disposal | Not mentioned | Daily cleanup, dumpster, magnetic sweep |
| Permit | Not mentioned | Not required for like-for-like siding; confirmed with the city |
What the worked example shows
Estimate A is not necessarily dishonest. It may reflect a contractor who intends to do the flashing and the barrier and simply did not write it down. But you cannot know that, and if the wall is opened and the sheathing is soft, Estimate A has no stated way to price the repair. Estimate B costs more on paper because it describes the whole job. Before choosing, send A back with a list: barrier, flashing, trim, sheathing rate, paint spec, cleanup. If A comes back with the same lines and a similar total, you have two comparable bids. If it comes back much lower, ask what was left out.
The same exercise works for every trade. The siding, window, roofing, painting, gutter, and dry rot pages on this site each list what a written scope for that trade includes, so you can use them as a checklist against any proposal.
What to look for, trade by trade
- Siding: the water-resistive barrier and flashing at every opening; which trim is replaced; a per-sheet sheathing rate; whether paint is in scope.
- Windows and doors: insert or full-frame for each opening and why; the product and its NFRC energy values; who handles the permit; interior finish work.
- Roofing: tear-off or overlay; underlayment type; every flashing, vent, and pipe boot being replaced; a per-sheet sheathing rate; how gutters are handled.
- Exterior painting: every surface named; how failed coating is removed; what is primed; number of finish coats; how rot found during prep is priced.
- Gutters: gutter size and material; downspout count and where each discharges; fascia repair; the guard type and the cleaning it still needs.
- Dry rot and trim: each damaged piece mapped; the replacement material; the flashing or sealing change that stops the water; a unit rate for damage found behind the visible piece.
What California requires in the contract itself
An estimate becomes a contract when you sign it, and California sets minimum terms for home improvement contracts. The Contractors State License Board's consumer guidance states that a written contract is required for home improvement work over $500, and that the down payment cannot exceed $1,000 or 10 percent of the contract price, whichever is less. The contract should carry the contractor's license number, a description of the work and materials, the total price, approximate start and completion dates, a schedule of progress payments tied to work completed, and the notices about your right to cancel and about mechanics liens.
If an estimate you are comparing asks for a larger deposit, has no dates, or has no license number, that is not a price difference. It is a sign the other document is the one to work from.
Questions worth asking before you sign
- What happens if you find rot or damaged sheathing once the work starts? Is it priced per unit now, or estimated later?
- Which parts of this scope are done by your own crew and which are subcontracted?
- Is a permit required, and who pulls it and schedules inspections?
- What is the expected sequence of work, and who is my point of contact while it is underway?
- Which manufacturer instructions or warranty terms apply to the material you are proposing?
- If I change a selection after signing, how is the change priced and documented?
Common reasons two estimates differ
| Item | Lower estimate often assumes | Higher estimate often includes |
|---|---|---|
| Preparation | Wash and paint | Scraping, repairs, priming bare wood |
| Hidden damage | Not mentioned | Per-unit price for sheathing or rot repair |
| Trim and details | Reuse existing | Replace with new, flashed material |
| Windows | Insert into old frame | Full-frame with new flashing |
| Gutters with a roof | Left in place | Removed, reinstalled, or replaced |
| Cleanup | Debris left for homeowner | Haul-away and nail sweep |
Red flags
- A total with no line items, or a scope that fits on one line.
- No mention of what happens when something unexpected is found.
- Pressure to sign today for a price that disappears tomorrow.
- Materials described only by brand slogan, not by product.
- A deposit request above the state limit, or no start and completion dates.
- No license number on the estimate. In California, the Contractors State License Board lets you check any license online, including whether it is active, bonded, and carries workers' compensation.
What to do next
Ask each contractor to fill in the missing pieces so both estimates describe the same job. Then compare totals. If you would like a written scope from 916 Exteriors to compare against, request an estimate and tell us what you are noticing on the house; the how it works page explains what happens after you do.