As with anything there are more the one way to do them. If the have doors on them it really helps a lot to remove the doors. If not the finished job will not turn out as good. The frame work can normally be sanded and painted in place. If the original finish is shinny of glossy this surface has to be sanded to allow the new paint to stick. their are primers available to help the paint adhere as well. Good luck hope my input was of some help.