Smell of oil leak 2003 porsche boxster

You have purchased a very complex piece of German machinery- you must budget for maintenance in a very expensive garage that specializes in these cars- you are in trouble if you are expecting to drive a Por$che on a budget-

Most likely culprit is the rear main seal. Oil leaks from there, escapes out from the join to the transmission and runs along the outside of the transmission and drips onto the exhaust. The cure is to remove the transmission, replace the RMS (and usually do the IMS bearing at the same time) then replace the clutch (if not Tiptronic) and reinstall transmission. Budget $3-4k for this.