I feel that 40 would be great if you can get it at that price..If they say no drop them to 33, there is no way that those 3 in the pic can take you even an hour, so that puts you just at $100 and hour.. So thats 16 groups of 3 so about 1500 for the day.. not a bad day.. And at 40 thats even a better margin
As you know those are easy to clean, make sure there is water at each building. But yeah 200hr or 1500/day is what we shoot for. If you are already doing stuff there and are adding this to your project you have more wiggle room.... $30 each.
That seems about right to me. I would not go under thirty five though. SHould be an easy sell. If it was me I would tell them that I would typically charge $50 each because they are considered a two story cleaning, but because there are so many of them I will do it for the single story price of $40