whats the best way of getting into these doors without it costing a bomb its the passenger rear the lock pin wont stay up for you to open it

Could be deadlocked? I had the same on mine, wouldnt open from either side. Apparently if you bang around the lock area while pressing the unlock button it can release it? I had no joy with it though. I had to remove the door card trying not to damage it too much, then prise the plastic lock mechanism apart and just fiddle with the insides till it finally opens. Can take 5 mins or 5 hrs, skoda quoted £160 for a new lock and opening door/fitting lock. Luckily i opened it myself and got a lock from a breakers for £10 :-)