Great location - Campo Santa Margherita is the best. Hugely charming and characterful apartment up a great many stairs, but in need of some TLC (tender loving care) and with some significant safety issues which I am confident the owner will address. He should also acquire some more and larger towels if he is to match standards set in other Venice rental apartments and avoid potential ribald comments from his guests!
We know how many towels are supplied when my wife's small apartment round the cornes is rented.