A. Unavoidable costs will continue regardless of the decision to make-or-buy, so therefore, these costs are not relevant to the decision.
B. Factory depreciation is a fixed cost and is not relevant, unless it is avoidable.
C. Property taxes are fixed costs, so therefore, not relevant to the decision.
D. Relevant costs are those costs that differ among related choices. Fixed costs that would be avoidable if a decision is made to buy are relevant to a make-or-buy decision.
