Moving out...need some questions answered! xxx?

me and my boyfriend want to move out. we have a few hunderes pounds saving ontop of like a 500 pound deposit.... we were hoping to just rent a cheap small flat for 6 months see how we get on with it however i dont know where to begin. how much i will be spending on living every month aqnd everything like that. could someone give me a rough estimate? and are there any ways that are cheaper ways to lower the monthly cost such as a shared ownership . im opn about �800 a month and so is he... im 19 he is 20 are we entilted to any working tax credits for being on minimum wage? or what happens if we lose our job while renting will we be covered by housing benefits? sorry lots of questions please help:) xx