I would say buy the cheapest one, it will start you in the trials game. Put £300 aside and pay £80 of that budget on a bike. when you decide yeah I like trials you then have an account with £213 in it probably because you spent the other £7 on sweets and you can put this towards a new bike. Or you could think this trials lark was just a passing muse and shot the bike down the local car boot for £20 to some gadgey looking kid with a mullet who says to his companions "'ere mett lukk at this bangin' bmx a got fer a score. it got tractor tyres n all but top speeds a bit shan like cos ring on't pedals is only lyk small init. dem brakes are keen as fook n all"
YOU WILL LOSE SIXTY POUNDS IF YOU TAKE THIS ROUTE
but you'd still have £213 of dead money kicking around in the back bag wheeeyyyy!!!