I am focusing on a scenario where an entity $A$ sell a service 1 to entity $B$.
Moreover $B$ also sell a service 2 to $A$.
The utility function of $A$ :
U(A)=price from B for service 1-price to B for service 2 + benefit from service 2 ;
while the utility of B is given as
U(B)=price from A for service 2-price to A for service 1 + Benefit from service 1 ;
If I use the same price function for both transactions ; what advantage would I get over two price functions.