That is very reasonable, I used to be a cleaner and in 4 hours I could:
Sweep and mop a shop (little on site spar)
Clean a large pub/diner area, this included picking up rubbish, hoovering, sweeping, mopping, cleaning tables and ash trays, shining brass, cleaning mirrors/glass, etc.
Clean 2 sets of toilets, ladies and men's, the front set and the back set, including toilets, floors, sinks etc.
A large area at the back including a big flight of stairs and a large room which needed hoovering/mopping/clearing due to people congregating there when the actual pub was closed.
I actually liked that job, it was very satisfying, not to mention the amount of money I would find
plus we got £30 every time we cleaned up vomit, I was like vom army people vom lol.
The only time I admitted defeat was after a xmas party, I had to call in reinforcements on that occasion.
If you are in Hertfordshire, I will clean for you, I'm shit hot as long as it is not my house
.