With negotiated transfer pricing, what is the minimum transfer price if operating at capacity? What is the minimum transfer price if not at capacity?

Minimum transfer price when operating at capacity is the marginal cost + opportunity cost

Maximum transfer price is marginal cost only, when not operating at capacity.

Explanation:

Minimum transfer price when operating at capacity is the marginal cost + opportunity cost because when operating at capacity there are 2 elements involved - the cost at which it has made the units it will be transferring to another department within the organisation, and the profit it would have made if it had sold those units to others (opportunity cost)

Maximum transfer price is marginal cost only, when not operating at capacity because the department is constrained, it can only produce for the satisfaction of internal demand, not external customers; hence there is no case of opportunity costs.