Cheeky way to cut service costs...?

[strat]

Since I am in the air force, if I ask the engineers nicely they can do a lot of the work that is normally done in a service for me. Obviously, however, they don't charge Flashman's prices - just a crate of lager!
Does anyone know if I can get away with having some of the work done by the engineers and the rest by a garage therefore still getting a stamp and also saving some cash?
I suspect I know the answer to this one, but its worth a try...
Thanks all.

[JSG]

No.