Rent to own is probably not what you expect. In this type of transaction the underlying assumption is the seller will be able to perform in addition to the tenant/buyer. Be careful putting up any large sum on a rent-to-own, most buyers and sellers are under the impression whatever deal they put together will be accepted by any lender when it comes time to actually purchase a home, not true. The mortgage underwriting guidelines are very specific and an underwriter may not agree with the terms on your original lease option. You may think all or part of the rent paid goes to down payment, not necessarily how it works when it comes time to get a mortgage and close the deal.
There is a lot of information on the link below. I hope my observations keep you away from harm, good luck.
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Financing Kentucky One Home at a Time
I answer questions about financing real estate based on my decades of experience dealing with mortgage underwriters. I do not offer legal or tax advice, if you need answers from an attorney or CPA find one knowledgeable in your local market.