Buying an idle car

Hey yall a family friend has offered me a 1997 BMW 540i Automatic for $800. It’s been sitting in his garage for 4 years and he hasn’t had time to work on it. He’s moving and can’t take this project car. It has a blown head gasket but apart from that major issue everything else is in great condition. Any tips on taking this project car? Where do I start?

UPDATE After looking through the comments, yeah you guys are right. I think I’ll get a bicycle at this point. Thanks for all the advice and feedback!