Preston's nightlife is ok. Nowhere near the level of choice you'll find in Manchester, but there's one good club each night at least, and of course plenty of smaller bars and pubs.
If you're someone who prefers more choice, Manchester's just under an hour away by train (the best travel option), with cheap ticket prices.
In university accommodation, rent is paid in September and again in January. Private accommodation payment dates differ from place to place, with many requesting rent in August/September, January, and April.