The accommodation varies across the campus's and it depends what your needs are.
For example, if you're going to be studying on De Havilland, then you'll want to be close by. Or if you're on College lane, then you'll want something there.
From personal experience, the De Havilland accommodation is pretty good and is close to campus, shops, and bar/sports facilities. The rooms are standard in size, have some storage, with good sized communal kitchens. The only downside being a very small shower (They are nicknamed test tubes!)
Here's a quick link to the main UH page with some information about the various accommodation offered.
If you have any further questions don't hesitate to get in touch!
Personally, I like college lane a bit more as it is more green with open spaces and the buildings are quite modern but it is down to you and your preference.
In regards to how rent is paid, your accommodation rent is taken out in line with your student finance maintenance loan. Let's say part of your maintenance loan gets paid to you on the 26th September. Your rent will then come out from your account a few days after this! (taken from the find your flatmates thread)