I can bet that almost everything on the car is original and at 150-160 k it'll need A LOT of work . Some people just dont care about their cars and they claim they can run these at a minimum like $500-700 a year but when you look at their cars all you want to do is throw up.
At 150-160 k kms you'll need to replace these, prices are just for parts
-All 4 rotors if they werent replaced $100 each (400)
-all 4 shocks are toast by now and shock mounts $750-850
-control arms 400
-rear trailing arm bushings 80
-diff bushings 150
-expansion tank and hoses 150
-both pulleys and belts 100
-if the window regulators didnt fail then they'll fail next week 120 each
-motor and tranny mounts are toast so are the shifter bushings 300 for all
and much much more
He says he has maintenance records, check them and see what he did change and go from there .
Dont be scared , these cars can be run at a minimum cost but thats just not how I personally keep my BMWs. But if you wish to keep that car in great shape then your first year you'll spend close to 3000 and every other year will be around 1500 including tires