Nguyen, Inc. has received a bid for $12,000$ units. The costing estimates show that the average cost per unit for this bid will be $$500.$ The company uses cost $-$ based pricing and adds $30\%$ markup to total costs. What total price will Nguyen ask for the entire order?

A$.$ $$1,800,000$

B$.$ $$6,000,000$

C$.$ $$4,200,000$

D$.$ $$7,800,000$