We planned to drive a 1991 Citroen AX to Mongolia. I've been driving this car for over 7 years and it never let me down. However in Europe this car is not worth $1000. Is it possible to drive this car and what are the consequenses if we don't raise $1000 at the auction? (we do have spare parts)

A Citroen AX won't raise anywhere near US$1000 in Mongolia. There are good cars coming in from Japan that will not have been subjected to the same stresses as your car, will be LHD and manufactured with easy to obtain spares (Citroen parts aren't easy to get hold of). Unfortunately, the CDPF won't be able to import that vehicle into Mongolia. There are lots of good cars available in the UK very cheaply and yet worth a lot more in Mongolia. Have a look at the vehicle guide to get some tips.