I have a small cleaning business in Florida and would like to charge my customer per job in stead of an hourly fee.

Are you a "general" cleaning service or something specific like carpet shampooing?

If you're doing general housekeeping, charging by Sq. ft. would be tricky at best. Would you go by room, entire home, etc? A bathroom may be the smallest room in the house, but could be the hardest to clean, requiring the most time. A bedroom could be over 500 sq. feet but only require minor dusting which no one would want to pay much for.

From a business perspective, you need to research potential competitors and find out what they charge. These things tend to be regional. Higher income areas will be more profitable. For example, those in Beverly Hills, CA will clearly pay more for cleaning services than people living in Smalltown, MN.

I was thinking entire home and general housekeeping nothing major.