I really do not recommend Lease with an Option to Purchase. Anything can go wrong, and you ending loosing money and time.
If you want to build your new home, and purchase the land for that home. Most of the land sales are in cash. It's not easy to get loans for land, but is not impossible. I can recommend some banks that can help you in that way.
Other option is to buy a house from a local builder. You can select one of the layout the already have, and incorporate some of the finishing according with your taste.
If you want more information, you can call me, and discuss the possibilities you have for you to be in your new home pretty soon.