I have found that usually there is no "rough" clean. What they want is for you to go in and clean it completely. Then they go through their punch list, have inspectors in, mess some things up so that you have to do a touch up clean. That is usually only a few hours of work. I would clarify with the builder if that is what he means, I bet it is if they are putting up these homes quickly and wanting to get them on the market in a hurry.