Inspection buy offs are an industry term related to getting an inspectors approval on work accomplished, sorry I shouldn't have used it since it doesn't really translate.

So Alaska required more inspector intervention than other airlines I worked on.

We use the term 'selling' and 'buying' to refer to presenting the work and demonstrating that it is airworthy (before we go to lunch, let's try to sell this to inspection, or, I won't buy that until you verify that it is torqued properly)

Think of it like you saying you cleaned your room, and your parents going 'i don't buy that'.

It has nothing to do with money.