I am very knowledgeable about 1969, and 1970 Mustangs. Having owned and working on my 1969 Mustang for years. I charge a fee for inspecting cars, and I take many, many pictures of the cars that I inspect. I also give a blunt opinion and report on the cars. I do not have very much specific knowledge about other years of mustangs. I would advise you find someone who is an expert on the specific year of mustang you are looking to purchase.
If the car you are looking at is a 1969, or 1970 than I may be able to help you. If the car is a different year I would have to decline.
Good luck! I hope you find a good one.