'84 E30 325e - A/C

Hi - new guy here. I have the opportunity to buy an '84 E30 from a good friend. The car has 130k miles and it was serviced regularly. He is asking for $2,600. The only apparent problem is the A/C does not work. Is this most likely a problem with the compressor? If so, how much should I reasonably expect to spend to fix the problem? I would like to buy this car, but I am afraid it is going to be a "money trap." Any thoughts?

Thank you.