Re: Air Con not working
is it aircon or climate? if it's climate then you will have extra sensors/electrical connectons that could be at fault. with both systems if the gas gets low there are a couple of switches around the pipe work that stop the compressor from working.
ask the guy to remove the battery and fully charge it, if the car starts, runs ok and the light's out then it might be ok. otherwise it could be a faulty afm/lamba.
jump starting can cause warning lights to come on, i have had the key code light come on before.
talking of that, make sure the guy has got the master key for the car, could save you a lot of money in the future if you have starting/ecu problems.