The information you need is readily available on the seller's monthly mortgage statement. Just tell him to look at the last statement, or show it to you, so you can see what the current balance is. That'll give you an idea if it's worth pursuing. The balance could be more than the ARV.
I just looked at one the other day. The ARV was roughly $175k, and I was hoping the balance on the reverse mortgage was under $100k. However, I took a look at the last statement and saw that the current balance was about $225k (the total payoff would be a little higher). Obviously a pass.
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