I do detailing as a hobby, charge only $30.00 or so for products used and then request the owner to consider a donation to one of two non-profits. I will usually spend 5 or more hours on the interior. The owner lives inside the car, so that is one area they notice the most difference. I also just take my time too. When I detail a car, I have it for two or more days so time is not a pressure issue for me. I have the fun of enjoying my hobby, get to work on some awsome cars, and my "customers" get their cars back with darn near show room clean interiors. Not sure, but I think most of them make generous donations to the non-profits.