I'd probably be fine with just getting a price per square foot. I just have a hard time with receiving an estimate that says "a, b, c, d, e" and I say, "I'll do c myself and don't want e" and the estimate is still the same. I know it's just an estimate, but it doesn't give me a warm and fuzzy feeling.
To explain further, our estimate included demo and 'countertops with backsplash' ($800 and $4500 respectively, plus another $1k for the bathrooms). After I asked them to itemize it (since I wasn't sure if we wanted the bathrooms, and the entire thing was rolled into one cost), we went to their office to pick out materials and they said backsplash would be an additional $1500. I told them I'd do the drywall after demo and we'd be doing the backsplash ourselves later (since we want to make sure it matches the house after the counters are in). I'm a bit leery about the fact that their estimates included "backsplash" but now it'll be an extra $1500. I emailed them to ask, and they're claiming this was just a granite backsplash (like a 3-5" piece you'd have in a bathroom). But who the fuck does that in a kitchen?
Anyway, my wife is now saying since demo in the original estimate probably included fixing our drywall, she wants me to just have them do it. Drywall is super easy, especially when I'm just going to tile over it, so I don't want to pay for that (which is why I asked about labor hours and materials). It's probably only a minor costs savings, but we're looking at somewhere between $6.5-7k in total spending already, and if I can save anything I will. Because that's stupid fucking expensive.