Sighten EverBright calculates loan amount from the install cost inserted by the user and the dealer fees set on the product.

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Loan Amount ($) = (Install Cost ($) - Installer Paid Rebates ($) -Upfront Payment ($)+ Dealer Fee ($)

Dealer fees are calculated as a percentage of the loan amount (not of the install cost), as a result:

Loan Amount ($) = (Install Cost ($) - Installer Paid Rebates ($) -

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Upfront Payment ($)) + Dealer Fee (%) x Loan Amount ($)

And with some simple algebra:

Loan Amount ($) = (Install Cost ($)- Installer Paid Rebates ($) - Upfront Payment ($)) / (1 - Dealer Fee (%))

Example

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