a 69 chevelle 395/350 4sp found me

[wiiildcat]

Dont know if this is right place to ask so if not mods pls delete this. My lawyer has a 69 chevelle, 396 350 horse 4sp car. he bought it in 89 from an estate. Its green on green, console, full gauges. Original paint all numbers matching and rust free, partial build sheet. Here's my questions, it has air shocks, I swear they look original but did they do such a thing? He wants to get rid of it and wants me to make a offer. The car has been in a shed, no heat since he bought it. He starts it 3 times a year he says but it hasn't moved in 21 yrs so I'm sure it needs stuff. I cant afford to own it but sure wouldn't mind flipping it so where should I be looking to offer him. Don't want to rip him off but don't want to be stuck with it either. Should have pics this week end any help would be great.