1999 VW Golf S 1.4L

My dad bought it for me last august for £1250. The car drives fine once you actually get it going so i'll just get straight to the problems with it. Gear box issues - it won't go into 1st gear and struggles to go in to 2nd. I don't know if its the gear selector or something inside the gear box.Battery keeps going flat - i've put 2 new batteries in it in the year i've had it, if you don't drive the car for more than a couple of days the battery just dies and i need to jump start it, eventually the battery stops working. (the one inside it is flat atm). Driver side door doesn't open from the outside, passenger side door doesn't lock, stereo doesn't work - the speakers worked just fine but the stereo just suddenly stopped being functional. 07891033358.