make sure the transfer case is working. do a jack test. Rear wheels up in the air and put the car in drive and see if the front wheels pull the car. that's a good sign. if not, bad transfer case or front drive shaft. control arms are far more costly on an IX then a regular e30. rust/rot behind the wheel moldings, lower fender heels. Moisture gets trapped in these areas making it common rust area. and the usual e30 stuff..LOL. sway bar links, tie rods, shocks. exhaust. rear license plate light area often rots out. aux fan seizes up due to a/c system failure. they stop using it therefore the fan seizes.
ALWAYS do a timing belt service and waterpump immediately if purchased regardless of what owner tells you.