How to figure out R2O numbers?

[Ilya Z.]

We were trying to sell our first flip but with COVID the buyer segment best suited for the house disappeared. Those are 1st time home buyers relying on Govt-backed loans like FHA, VA, USDA etc.

So what we've decided to do to reduce the bleed is to find a short-term tenant to rent to, and then put the house back on the market after things improve (will it be in a month? 6 months? 6 years? :-))

We would like consider a rent-to-own option. Question is, how do we figure out the numbers? As I understand, a R2O deal would include an upfront deposit of $X that would count toward the eventual purchase after Y months/years, which the tenant would lose entirely or partially if they decide not to buy. And there's also an option of increasing the "pure rent" by $Z/month with that difference also going toward the purchase. So how do I figure out what X, Y and Z should be?

TIA!