Should I be wary of buying a BMW 5 Series with mould on the seatbelts?

I'm interested in buying a 2013 BMW 5 Series Touring but I've noticed that it has mould on the drivers seat belt and the driver's side rear seatbelt. The dealer said that it's condensation from wet floor mats left after valet. I don't know if it has anything to do with the fact it has a panoramic roof because of possible leaks. When I lifted the bonnet it was surprising clean. On questioning the dealer, they said it'd been steam cleaned. Am I right to be wary of this car?

Asked on 23 March 2017 by Vm

Answered by Honest John
I'd never steam clean an engine because it takes off protective wax and gets into delicate electronics. The damp inside could be from the valeting. But there's another reason why the F10 5 Series get damp inside. The hole in the bulkhead for a LHD steering column is merely blanked off and if the bulkhead vent well drains get blocked, water from the vent well gets into the car through the blanked off steering column aperture.
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