Yes we do a few - basically we try to arrange for a Saturday then it's tagged onto the end of the week depends on the caretaker.
Failing that it's usually booked well in advance ( 2 months or more ) and I schedule domestic rounds to suit a school clean would go ahead on that day unless it was extremely bad weather
Be warned they are very hard work, find out when the last clean was usually it's more than a year ago and who ever done it last most likely did a pretty poor job!
If it's got lots of a acrital (metal) frames prepare to clean them twice when WFP ing
Nice add on if you get the right price, but don't fret if you miss out and don't quote too low because you'll hate it!
Darran