Spent $4,200 on my first flip on things that don't show up in photos

I'm still building my list so take this as one, but every scope sheet I've been shown has a line called something like site costs or general conditions. Dumpsters, portable toilet, cleaning, lock changes, utilities while you're working. It's real money and it's never in the pretty categories. 4,200 on 26,000 is about 16 percent and the numbers I've seen quoted for that bucket sit around 10 to 15 percent, so you're a bit over, mostly because of the water heater permit which sounds like it wasn't yours to plan for.

Yes, name it. On our jobs it's a separate line and the client sees it, because when it's hidden inside the paint number the paint number looks insane and nobody trusts anything after that.

The snapped shutoff is a different category. That's the cost of touching an old house, and it happens whether you planned or not, which is what contingency is for. 10 percent contingency on a cosmetic scope is thin in my experience, 15 is more honest.

@quarry the thing I'd watch is that permits and what triggers an inspection vary by city and state, so the water heater one may or may not have been something you could have found before closing. Worth asking your municipality what open permits exist on your next one, before you're under contract.