New here as well but did make the jump a few months ago and picked up an 08 LP640. The items I'd tell you to watch for are the basics and it seems like you are not new to this - Carfax, repair history, service records. Some things that showed up to me when I got mine were simple things but on Murcies the repairs can add up quick. Seepage around the rear main would concern me a bit, especially if they had the engine out to do the clutch; why was that overlooked, "missed" or was it just a clean it up and try to sell it off quick so its not their problem because it "has a new clutch!" New rear main seal should have been around $1k, so what else was neglected? Those would be the questions I would be asking.