Depends on the surface.
Concrete, £2 psm
Blocking, £4 psm
is what we charge.
Some will be more expensive, some will be cheaper. Cheaper again if there's loads of metreage.
Depends on machine too. You would probably be best to guess a couple of jobs-you may lose a few quid/hours-but time yourself and take an accurate measure of the surface and work out what you'd be happy earning an hour. It's the only way you'll know what YOU want to earn using YOUR machine, not what other people on here are happy with using their kit.