Fha Reverse Mortgage Lenders Aarp org reverse mortgage calculator How Many Types Of Reverse Mortgages Are There What is a Reverse Mortgage – Reverse Mortgage funding llc (rmf) – A reverse mortgage is a home-secured loan that can turn part of the equity you’ve built up in your house into funds you can use today, or a line of credit that will be there when you need it.This calculator is an example of those hosted on reverse mortgage lenders’ websites, and it’s a little more detailed than AARP’s. Consumers are asked to enter their zip code, mortgage balance (if any), home value, name, and date of birth for themselves and any co-owners.