Ben,
I believe that there are two questions you have to answer, and then I'm going to respectfully disagree with one of the other suggestions you were given:
First, (and I believe Jim identified this issue) is your transaction a true lease option or is it a deferral of part of the purchase price, including payment of a finance charge? (a loan) What you described sounds like the latter. (making it subject to TILA and NMLS reqs)
Second, are you a "creditor" under TILA ?(Truth in Lending Act) I would think you are, the correct answer to the first point leads to the creditor definition.
A "creditor" under TILA is an entity or person who extends consumer credit with a finance charge more than once in a 12 month period, which you likely do.
I will disagree that "licensing is easy to get," as the NMLS test is hard to pass AND even if you do, your entity must now begin quarterly and annual reporting to the NMLS System.
Also, under Dodd Frank, if the above apply, you are probably required to document the borrower's ability to repay, and service the credit agreements/loans under the strict Dodd Frank loan servicing rules.
In Dodd Frank, they anticipated that some might carry paper to get around Dodd Frank (not that you are doing this) and therefore they also "cast their net" over seller carry backs.
Most importantly, please don't rely on what I say, except to inspire you to seek legal advice (which I am not qualified to give) from a qualified attorney in this area, and structure this so it doesn't get you into legal tangles or possibly worse, interaction with the CFPB. (no fun)
I do testify in court as a mortgage lending expert witness, so I am at least qualified to say that when borrowers can't make payments, they often sue or otherwise challenge the legality of your loan origination.
Hope this is helpful. (although not fun reading) I do like your business model.
Joffrey Long
www.MortgageExpertWitness.net