How is prepaid maintenance plan refund calculated?

Before going to the dealer to cancel it, I want to make sure the numbers are clear.

The PPM is charged at $1100. The MSRP is $850. The dealer mark-up is $250.My lease RV% is 63% (or 64%?), and tax rate is 9%.

So the refund should be $1100*(1-RV%)1.09=$443.63?
Or, $850
(1-RV%)1.09=$342.81?
Or, ($850
(1-RV%)+$250(mark-up))*1.09+=$615.31?

Thanks!

A post was merged into an existing topic: How to cancel MB prepaid maintenance plan?