Hi Andre,
A cost center can be related to the following organizational objects:
· an organizational unit via relationship A 011 (Cost center assignment)
· a position via relationship A 011 (Cost center assignment)
· a work center via relationship A 011 (Cost center assignment)
Costs incurred by an organizational object are usually written to the cost center directly assigned to the object (master cost center) or the cost center inherited by the object from a superior object. Determine the master cost center in infotype 1001.
What you see in PA0001 Table under filed KOSTL actually is defaulted by the the position occupied by the employee , To answer your question
1. Where to look for employees cost center : IT0001 under KOSTL Filed,
you could assign cost distribution using infotype 1018 if you wish to distribute costs to more than one cost center or for cost distribution you could also use PA infotype 0027 for distributing cost i.e. employee salary (50% or 100% etc).
2. Which should take preference :
Master cost center, you could distribute the cost to different cost center though.
Hope this helps
Regards
Sid