I have approx 15 plus a full glass conservatory, a double sliding patio door and a glass front door.
I pay a guy £15 every 2 weeks. He uses a pole thingy and does a very thorough job.
Money well spent in my case.
We probably have more if you count each bit as a separate window - but at least that number
many years ago - about 13-14?? - a firm came round and offered to clean them for £10 so I said yes
then a few years later he decided to sack some of his workers and hire some more for cheap (do I hear someone muttering "minimum wage" and "illegal immigrants"???)
anyway - the bloke that was actually doing mine every month decided to start his own company and went round knocking on the doors of the places he had been doing
He is a nice bloke - I see him sometimes when riding around the canals - and so I said I would switch to him
he is still doing it all for £10
he really should increase the price but he has not as yet - I actually feel I should suggest it to him but........
anyway - they initially used the old ladder and bucket system but switched to the pole one a while ago
they do a damn good job so I stick with them