What if it needed the worst access and expensive issue fixed with the engine ?
What if you had to pay ? Or fix it yourself ?
Research that engine in that car for recalls and TSB's
They tell you the MFR update. Automotive databases or the dealer is where you can ask and or read about what goes on with them.
If it's worth having in your future, you can spend some time at a library even, finding out.
A car with a leaky oil sender is really probably the most common.
The updates for valve cover can be the part they use for the update.
Your mechanic needs to run a dye test to honestly give you the actual source of the leak.
Having the car inspected and or diagnosed before buying it is not only your right, but your responsibility to yourself.
And everywhere you drip oil all over.
Lets say you just had a gasket thrown at it, and a sender.
Cheap, right ?
Except it is a VW. make sure your parts are right and for the right make, model, year, and engine size.
I go thru this with my german built car,
Autohaus.
Your needs depend on your actual model, and anything different about it.