buying a 05 tdi avant

hi eyeryone i,m a newby just joined this forum (looks great)
not had time to fill my profile yet

but i,m under a bit of pressure as i,m about to buy a 05 plate tdi
the guy as give me the car for a day or so to give it a try
now what i,ve found is that the airbag light is on and when the car is ideling i get a bit of a judder
apart from this the car is mint with full audi service history and any work that has been done was done at audi
but not seen any paperwork as yet
are these to thing that are wrong anything to worry about oh and the car is on 106,000 mil;es

any guildance i would be grateful
cheers Derek

thanks guys something to be concerned about then should i take it to audi can they tell and advise?

if i was to buy the car and the oil pump balance shaft has not been done should i get it done streight away?

anyone got an idea how much for this job?

he told me the cambelt has been done and he said anything that needed doing on the car it went to audi

thing is this car is great and i dont want to let it go as everything else is mint