As everyone will say - don't get into debt if can avoid it, but if you must here is some of the info i have learn't over the years;

You can request a settlement statement and pay most bank loans back as soon as you like - but just watch for charges and always take the time to read the small print. Most loans are loaded with interest so you pay the majority of interest up front and don't start paying majority of the actual borrowed sum of the loan off until further into the repayments.

Best bet is to speak to your bank about exactly what you require, but do get other quotes as they are giving credit away nowadays and you can get some good deals; lenders i have had good dealings with are Northern Rock and Tescos (Royal Bank of Scotland). HTH