I would instead recommend you figure out why you can't qualify for a mortgage right now, and make sure you're getting good advice on how to make any necessary repairs to your credit so you can move forward with a normal purchase transaction. Also, if you need a down payment, there are many programs throughout the State of MN to help you. If you need help accessing these resources - just let me know.
Thanks for your question!
One of the biggest problems with this kind of contract is that it blurs the lines between Landlord/Seller and Tenant/Buyer. Minnesota Public Radio has a great article on the issue.
Consider this... If you decide to "Rent To Own" - let's say you make a $3000 downpayment but then one day you find out your property has gone into foreclosure because the Landlord/Seller stopped making payments to the mortgage company. Do you get your downpayment back when it goes through foreclosure? Not likely. Also, who pays if the furnace goes out or someone breaks, who pays to have it fixed?
While "rent to own" sounds attractive, it is very problematic.
You may want to consider just renting until you are able to purchase - that way you will have the full backing of the Minnesota Landlord / Tenant laws to protect you.