I had a look at a house today, I spent ten minutes looking round with the owner and put in a price for £600 for the first clean in and out. She didn't bat an eyelid and thought that was fairly realistic considering the size of it. Repeat cleans will come in at £80 - 120 external no less than quarterly, with specials between for visitors and parties etc.
It is a big place with glass balconies on three floors, each one must be 15m long. The top floor suite is fantastic with two full glass sides and a massive balcony deck. The bulk of the glass is on the front of the building which looks out to sea and catches every bit of sea spray going.
The place is just being snagged by the builder after 12 months building, so a full builders clean is required, which is a shame, but for £600 I should get it spot on and have another nice job.
Its nice when people with a bit of cash call out of the blue.