1. Walk the room together
Look at the existing layout, note what's original to the house versus already updated, and get a read on access through the rest of the home.
2. Separate what's cosmetic from what's structural
Builder-grade fixtures wear out on a predictable schedule; the framing, drain location, and waterproofing behind them are a separate question that needs its own answer before a scope gets written.
3. Put boundaries around the job in writing
Materials, access logistics through the rest of the house, permits, testing, cleanup, and how a mid-project change gets priced should all be spelled out before a hammer gets picked up.
4. Weigh the reasoning, not just the total
Two proposals with the same bottom line can cover very different amounts of actual work — read how each one explains what it includes and what it doesn't.
5. Walk it one more time before anyone leaves
Confirm testing results, cleanup, paperwork for any warranty, and whatever maintenance is now on you going forward.