Stopping Foreclosure on a Decedent's Property

[Jared Hennings]

I'm working a deal where the property owner passed away in March. The property is in pre-foreclosure with a scheduled Jan 3rd auction date. I've contacted her sister--who says she is the sole heir. my plan is to help the sister get appointed as executor, halt the auction, and get added to the deed. 

Does anyone recommend a type of agreement I can sign with the sister so that she is required to sell my company the home?