1990 supra turbo To buy or not to buy

[spunkenhimer]

Here is my predicament I've been talking to this guy thats trying to get rid of his 1990 supra turbo its got about 18000 miles on it and I've test drove it and it rode well and felt fun to drive. The only thing thats making me second guess myself is that while riding and driving the car I smelt something but I couldn't tell if it was oil or just the smell of the interior, or something else. I just wanting to know cause the guy said that the car engine had been freshened up not rebuild. Also that he had done some work on the car himself but nothing major. Hes asking $2500 for the car and i just want to know if its a good deal and if there is a problem with the engine...such as leaking oil what could it be and how much will it cost to fix if i do it myself?...(I am somewhat mechanically incline.)