A suggestion I have, but have not done yet myself, is to go to a smaller store with a fair amount of shopping carts and offer to do them for free. This can do two things for you. It can give you experience doing them and it can maybe pick you up a new client. You then can get an idea of how fast you can go. I know Delco's guide says to charge anywhere from 75 cents to $2 a cart. That is a broad range. You wouldn't want to tell someone $1 a cart and find out you can only do 30 an hour. On the same note you don't want to say $2 a cart and find you can do 100 an hour and they don't hire you because your price is too high. Do some demo work to see how long it takes you. I want to a little store with maybe 100 carts and see how long it takes. There will be no pressure on me because it is free. But just remeber that you will gain speed. Also take into consideration if you have to move the carts or are they? I just started doing car lots. The first time I did two lots. 6.5 hours to do 70 cars. The second time I did 78 cars in 4 hours. This week will be my third week and I am sure I will shave even more time off that. We take a little longer but also we get paid more per car too. If a lot wants to pay $1 per car they get a $1 wash. When they pay $4 a car they get a $4 wash. I will be trying out the cart thing in the next week and I will post what my numbers turned out to be.