Pre-purchase diagnostics - oil leaks from the engine crankshaft seal

[s0ma]

Hello there.

Long story short - before buying Honda Civic (hatchback) 2.2 ctdi, 2011, (168 000 km mileage) I sent it to official Honda Civic service for pre-purchase diagnostics and there where issues with:

• Oil seeps (no leakage yet) from the engine crankshaft (front) seal
• A small steering mechanics free-movement (small wobbling)

I know how much the steering wheel support repairs will cost, but my main question is - what are most common/probable reasons for oil seeping/leaking from the engine crankshaft? The service wants me to pay for additional diagnostics service just to check the engine and why is the oil seeping.. so I would like to know your thoughts about this. I don't want to invest into car, that may have some serious issues with the engine.. just to throw additional few thousand on top for repairs.

Thanks in advance.