Leasing with an option to buy is usually a tricky feat. Lots of sellers will be willing to lease the property for a predetermined contract term without making an appealing option. If an option is made, it's very hard to determine what the value of that option should be. If you sign an option up front to purchase the home after the the lease term expires, the property value may change before that lease expires. This can work for good as well as bad depending on the trend of the market where that property is located.