If your parents sell you their home for $100,000 and it's worth $300,000, their gift of equity equals $200,000, the difference between what they're selling the home for and how much it is actually worth. A gift of equity is valuable.
The seller must obtain an official home appraisal to ascertain fair market value and also sign a gift letter that describes the buyer-seller relationship and states that the equity is a gift the buyer is not obligated to repay. The buyer must follow the typical process for buying a home.