Guess how much some numpty, has charged for the following...
Two blocks comprising 18 flats, over 3 floors (grnd 1st 2nd)
66 windows, 22 per floor and 18 balconies 6 per floor.
Including inside the communal windows in the 2 lobbies. Takes about 3-3 1/2 hours wfp. And you have to arrange the day, and be there at 9 precise to do the top balconies.
I had been doing the job for 4 years, it's next to a bigger contract so I did it for a very reasonable £112.
They asked for 3 fresh quotes because they are skint. I went in at £80.
Any takers? Guess what it went for.....
£65 every 6 weeks 
Some people are muppets
If it weren't for the access restrictions/balconies, I reckon that could be an OK price for such a job (£65 for 66 windows plus a few internal communal windows?) .
I do several blocks of flats together in one contract. Twelve flats in each block spread over G,1, and 2. A bit of inside window cleaning on entrance doors and upstairs windows. The first clean was a money loser (more correctly - a low hourly rate for a self-employed sole trader) because I did it properly but the three blocks are half a day on their own if I work pretty hard. Not saying the price on a public forum but it's in the same ballpark as your old price for your two blocks. It's 168 windows plus a little bit of internal - all easily accessible.
I think it's those balconies that are the problem. There are none on the blocks that I do. Nor are there any full length windows with railings. Without such obstructions, it's possible to fly around such work once the first clean is out of the way. It's certainly not my best paying work hour for hour but it's one decent chunk of money from a very prompt payer and it's close to home. I also think it can depend on what equipment is being used. I use a lightweight carbon telescopic pole as I can reach everything with it.
OK so it ends up being a hard half day for somewhere around the £112 you mentioned.
So somewhere around £28 an hour. Not so good hour for hour as some work but OK for the type of work that it is.
The rate would certainly go up if there were access issues or any unreasonable time restrictions as that can be very time consuming.
I certainly don't regard myself as a muppet

signed
Kermit.