damn mate, sounds like a shitty land lord then, the problem is with moving is finding somewhere that you can continue to do what you do, at least your landlord is ok with that, holding you to ransom for water is no good, good job you dont go round wasting it, isnt their anyway you could have a water butt and collect rain water and just use that for the garden, chances are you all ready do this, just trying to think of ways to help you mate