With my car just over 105k miles, i have noticed this week when changing the oil, there is a leak from between the engine and the gearbox, this usually indicates the rear main seal is going.  Yesterday I looked at the undertray and there is fresh oil sitting on it, so I have a pretty serious rear main seal leak.

 

Does anyone have any ideas on how much this typically costs to replace the rear main seal?

Just for info: if this is a 1.2 TSI, when I had one it developed an oil leak between the engine and gearbox due to defective flywheel bolts -- so another possibility. Unfortunately I don't know any more specifics, only that it had also been seen on a number of Polos with the same engine. (In my case this was sorted under warranty, so no idea of the cost.)