What are typical repairs might I encounter as a dirt bike owner? I am planning to buy a 2006 YZ250 Yamaha?

[berrytrain]

It has only been ridden a few times according to the seller
(this seems to be a common theme, which makes me question its validity). I don't want anything which is going to
require repairs on a regular basis. What are typical dirt bike
mechanical needs, and repairs? Thanks.