Hi,
These are all basics, allready there are so many post on this requirement please check, but still I am trying to answer your questions...
You can classify your cost centes as. 1. Service Cost center 2. Oh cost centers 3. Production cost center.
There is thumb rule in cost cener accounting at the end cost center balance should become 0.
a. we can 0 service cost cente balance by using Distribution and assessment.
b. Over and cost centers cost we can knock of with Over head% and if still balances are there we can Transfer to production cost center or COPA.
c. production cost center cost will get knock of at the time MFN1 / CON2,
If you you want to get the credit to multiple cost centers then create the multiple credits and assing in costing sheets or Use the user exit COOM0001 .
Regards,
Ram