Cashley

So I just purchase 4 months ago, 2008 Cayman base, 85,000 miles, previous owner kept amazing maintenance records. Vehicle checked by mechanic and all was good. I also took a good look and everything look good and dry just a bit dirty as the car saw a couple winters. Have put a couple 1,000 highway miles on the car and found a drop of oil on the garage floor. Rear Main leaking or am I looking at another issue? Many thanks