You have seen it in person so all you need to do is figure out whats needed to complete and based on your evaluation make an offer. I would offer $3000.00 max. Can you finish the car meaning putting it together, if not figure a good Z tech who could finish it. Do an autocheck or a carfax also. If you do not feel comfortable take an expert with you.. Rust is another story... check undercarriage and brake lines etc..in one of the pictures there is lady leaning against the house, if thats his wife, her face is telling me please buy this damn car and get it out of my life.. lol...so she might help you buy it cheap.. lol..