Bartley Manufacturing incurs unit costs of $8 ($5 variable and $3 fixed) in making a sub-assembly part for its finished product. A supplier offers to make 10,000 of the part at $5.30 per unit. If the offer is accepted, Bartley will save all variable costs but no fixed costs. Prepare an analysis showing the total cost saving, if any, Bartley will realize by buying the part. What should they do?