At my uni you can apply for a permit for £240 (they only give out 50 student permits a year though, and we have something like 16,000 students) or you can buy daily parking vouchers for £1 each. Makes way more sense to buy the daily vouchers because even going in every day of term wouldn't cost £240 a year haha. I don't do either of those though, there is a free parking bit in a residential area that is a 2 minute walk from campus, so I park there.
Unless you mean for halls, then I have no idea. I have a few friends who had their cars at halls and had spaces there, but I'm not sure if they were allocated on a first come first serve basis or how it was done.