Nat,
We dont touch the domestic side at all, but when you employ staff they have a whole series of rights as an employee.
Any member of staff is entitled to holiday pay, your prices to your customers must reflect this.
CRB checks are also advised, especially for lone workers in domestic premises, dont forget that you need to comply with the "Lone Working Regualations" to satisfy H & S as well, again this needs to be costed into your charges.
Regarding "hiring, self employed cleaners" as suffolkclean stated, this is not really on, but you would be shocked by the number of people who actually do this sort of thing all the time, most of the time they do unfortunately get away with it, but if something goes wrong........
Taking on staff, even one or two, is a decision that should not be taken lightly, the tax people etc, will tell you its really nothing to be concerned about, but you must be very careful to have systems, policies and procedures in place to deal with all eventuallities. Contact your local Chamber of Commerce, Business Link etc, and get yourself some real advice from an employment specialist.
Regards,
Rob