Selling to someone that doesn't have money now

[Brett K.]

I have a property I want to sell and a buyer that has money tied up in an estate.  Supposedly a substantial amount of cash will be inherited in February.  The rest of the money that will be needed to purchase my property will be from her mom's home that is currently for sale.  

The negatives are:  She has no savings, she wants to move in as soon as possible, she is getting rid of bed bugs were she's renting now (Sec. 8), the purchase money will come in two large chunks and I'll have to wait months.  

Positives:  she's offering asking price and the market is dead in this neighborhood.  

I'm not sure how to structure this deal and I'm worried about letting her move in without a substantial chunk of cash for my security.  She loves the house and I'd like her to have it but the thought of her moving in and not performing....