The way I have structured the lease amount is to have it cover as much, if not all of the current mortgae due with an option amount above and beyond the lease amount that an escrow office will hold until the end of the contract. The option money is to be used as down payment money if the buyer excercises their option to buy. If the buyer does not excersie their option for purchase then the option money will be released to you the seller.
These can be complex in that you do take the risk on of a tenant and you also want to keep in mind that the buyer may not excercise the option to buy be cabable of buying at the end of the term. Make sure your option maney is enough to protect you should the buyer not go through with the purchase.
Hope that helps,
In a lease purchase, you become a landlord, which has issues of its own if you're not prepared for them and especially if you're moving out of the area.
A lease purchase is an option to disposing of property during a slow market and there are plenty of potential buyers out there seeking these opportunities. So simply publicizing that you are welcoming "lease purchase" offers should generate serious interest.
As a seller considering a program of this nature it is advisable that proper precautions are taken to protect your interests by preparing the proper contract to cover your transaction and by getting enough of a deposit to protect your interests should things not work out and you need to reclaim the property.