so what do you use that mapet nance check list for? -- maintenance check list for? >> for every project we finish, we sign a service agreement or offer a service maintenance agreement and then when we go back to the house a year later we go through this check list and we go through the whole thing to make sure everything's being maintained, that, well, it's a very detailed check list. but every house in san francisco needs to be maintained and you can see through lawrence's slides what happens if you don't maintain them. >> in my experience, often people do wonderful design work and excellent construction but stop at that point when the construction is finished and think they're done. but that's not the case. you have to maintain it. you have to have a program first to evaluate it. is this what we wanted? pick up the stuff that's not quite right, you thought it was ok but not. so we have to do post construction evaluation and then we have to have a maintenance program. you've got to maintain them. these houses do not maintain themselves. and much of the work that we