Classic/Antique Car Repair: mercedes 450sl 1975, mercedes 450sl, flat shapes

Question
Found what a Mercedes 450SL 1975, automatic, original (?) 68,000 miles and $7900.00.  It was blocked in on a car lot and heading back tomorrow to test drive it.  Am I getting into trouble (financially) considering purchasing this beauty?  Have no experience with classic cars (this car was IT when I was a kid in 1975).  Things to look for? Or look out for?  Thanks for your time.  
John - Classic Dunce

Answer
I am not a financial advisor. Believe it or not, my wife paid substantial money for a clear ROCK someone found in the ground in South Africa and cut in funny little flat shapes. She actually wears it on her left hand and is very proud she paid that much for a little rock found in the dirt. She is happy with it. If you feel the same way, does not really matter.