Lease calculator

Hello, the lease calculator you have is almost perfect for what i need.

There are 2 things I’m hoping you can help me with.

1. I would like to have a toggle which can change calculations from payments in arrears, to payments in advance.

2. I would like to have the residual value field as a percentage of the loan amount instead of a fixed value.

Is this possible?

The page I need help with: [log in to see the link]