Depends how much discount you are going to get for paying up front I doubt if it will be equal to 1 months rent!!. You can actually sign a contract for a year, but pay 3 months at a time in advance (so 4 payments). I guess you can actually pay monthly in advance, if the landlord is willing. As to what protection you actually get (through the courts) I would suggest that, practically, it is really very little. It very much depends on "good will" - unless you are willing to spend nearly as much as you have lost on legal fees
My last landlord sold 10 months into the contact. New landlady said she wanted to move in 14 days before my lease was actually up - I said to her "Fine, as long as you give me half a months rent back". Stayed until the contract ended. But still ended up with huge hassles trying to get my deposit back (took three months

). Deposit will be more than 1 month rental, somewhere between 1.5 & 2 -really depending on the quality of the fixtures & fittings - less if it is unfurnished.
Personally I wouldn't pay for a year in advance, upfront, there are too many variables - neighbours might be awful for 1, area might be far noisier than you imagined, you just might decide you want to try somewhere else..