@ Said as a supplier you are allowed to act as agent to 3rd party service providers in your industry.
Clients don't like hustle, so you bring 3rd party services like AA to their doorstep.
BUT as you do so,make the client aware of the existence of 3rd party costs and whose responsibility they are because they will claim that 'you didn't advice them'as the expert..NEVER assume they know.


Typical scenario;
Client wants A from you, but without C from a 3rd party she can't get A so;
1.She can get C direct from 3rd party with all the hustle or
2.She can get C through you but at a small fee or none-just have email proof and receipts.

Either way C must be paid for by client cz it's not your cost.
Talk to her nicely.