F40 Advice

I am fairly new to the site. I am based in the UK and am interested in purchasing an F40. Having owned modern F cars, I am unfamiliar with what to look for on the beauties. I dont intend to track or race the car but use it on occasion and for investment. Any help on what to look for and advice when looking at potential cars would be grateful. Are they reliable and what are the pit falls to look for including the right spec to chose. Any help would be gratefully appreciated including buyer tips. Appreciated and thankyou in advance.