Housekeepers? In addition to my new art I have decided to do some...

In addition to my new art I have decided to do some housekeeping to compensate the bills while business grows. I want to do this in an organized fashion and engender sure that I am paid according to what I do and the clients are not over/under charged. Any advice for fees? I am thinking of charging by the room next to a minimum. I feel that this way the position and cost is custom for each client and they are not paying the same for four rooms as somebody near six is. I am also looking for some resources such as a good cleaning supply checklist and cleaning tips. Also any tips from people whp own done this are always welcome. Thanks a bunch :)
How can I bring a black pen...
Answers:    I wages my housekeeper $20/hour. She is here for about 5 hours, every other week. That's $100 for 3 bedrooms, 3baths, kitchen living room and dining room. I also give her a Christmas bonus equal to one call in: $100 plus a small gift.