Hi
add custome condition type JCBD in your pricing procedure and assign the pricing procedure to service vendor in purchasing data and also need to create a new vendor as custm vendor and add in the procedure like
go to conditon tab in the service po and select jcbd condition type and select the details maginfier and add the newly created customer vendor in the bottom of the screen.
it custome charges will be paid to the that vendor ( same process for freight /courier)
Regards
Sudhakar