A recent article in Motorcycle Consumer News told of the woes that are possible when buying a pristine, older low-mileage bike. I think the bike in question was a '99 or so VFR. It looked perfect, but the after-purchase inspection revealed that all of the rubber bits were dried up, and the air filter was a multi-unit mouse apartment complex. If there article wasn't a hypothetical, the new owner ended up donating the bike rather than repairing it.
My in-laws live on a farm in rural San Diego county. Their car is parked outside, and is perpetually being chewed on by mice, and oddly enough, the engine is covered in snails. One of my jobs whenever I visit is to check all of the car's functions and lights, and make repairs and patches as necessary. I have put about six mouse traps in the engine compartment.