gift equity in purchase of a family home

[Ryan Flater]

I am planning on buying a home from a family member the home is valued at $700,000 and I am buying it at $500,000. At the close of escrow I am to sign a lien document saying If I sell the house with in 10 years I owe the "gift equity" back. My family is extremely hard to deal with and cannot leave emotions out of business. Is there a way to set it up so a third party controls the lien so that if I sell the house I do not have to deal with family but a 3rd party