How do I adjust the Financing Program Dealer Fee to Account for Sales Tax?

How do I adjust the Financing Program dealer fee for sales tax? (Fig. 1)

If your dealer fee is 7% and your sales tax is 8%

Multiply 7% x 8% to get 0.56% and add it to your dealer fee.

Your adjusted dealer fee becomes 7.56%

Figure 1. Sales Tax Adjustment to Dealer Fee.