Whilst Lancaster is hardly a top tourist destination, it does have some things going for it for travellers, as well as students. I have wrote this with both groups in mind.
Whilst short term accommodation is very expensive, it is quite cheap if you can stay around for a few months. Rents are low. Rooms are widely available, for students or non students. You should be able to find one quite quickly. However, they are rarely available on short term leases.
For working travellers or students, employment is either incredibly hard to get or incredibly easy. It depends on what you are looking for. During term time, part time and casual unskilled jobs can be found quickly and easily. There are numerous positions as waiter/esses, bar staff, cleaners, kitchen assistants, call centre workers etc. All are low paid and have a high staff turnover, meaning that there are vacancies everywhere. This is an excellent place for travellers to supplement their trip funds. In addition, all of that evening and weekend work means that you will save money instead of spending it on socializing! Many of these jobs are paid cash in hand. However, there are few full time jobs.
EU students can work freely. Other international students are not supposed to work on their visas, but some do manage to get work off the record and cash in hand.
The high student population sometimes leads to tension in the town. The resident population is far lower. The town is geared to the interests of young people and student needs, but sometimes to the expense of other residents needs. Some resident hostility is justified as student behaviour sometimes is very inconsiderate of others. The majority of students are fine.
If your not a student, you can still take advantage of the student orientated facilities in most cases. Restaurants and bars almost never ask for student ID, so you can still enjoy the happy hours and drinks specials. Nightclubs are a different matter. Student nights involve either cheap or free entry, and cheaper drinks than usual. You will need to produce student ID at the door normally. When shopping, many shops offer student discounts. You will need to show a card when you make your purchase.
Student ID cards are very easy to get hold of, even if not a student. I would recommend one if your travelling around the UK. Sometimes just visiting a campus travel agent is enough. Or, try signing up for a part time or evening course, which provides the registration.
Lancaster is no more dangerous than anywhere else. If your alone, avoid the Millenium Bridge at night. There has been a spate of muggings in that area recently. During the day it is fine and always busy with lots of people. Lone females should take care in the Moor Lane area late at night. Last year several women were raped around there. The rapist has never been caught, but there have been no reports of attacks for a year or so. However, I would advise lone females in that area to return home by taxi if it is very late at night. On Thursday to Saturday evenings, from 11pm onwards the town is full of drunks. I don't like being there alone at that time (I am female), though some people are not bothered. Most of them are more irritating than dangerous. Fights can occur quite easily, fuelled by large amounts of cheap alcohol. By all means join the rest of the party revellers, but take care to stay safe with it.