Has your tenant buyer been prescreened by a mortgage broker to see if she can qaulify for a mortgage for your asking price and also how far out she is from getting qualified?
I suggest that you do that with all of your RTO tenant buyers. That's a requirement I have with everyone on my buyers list. Anyone who wants to take a house has to be prescreened first or I won't let them take it. Follow up with guidance emails on credit repair and debt management and add in affiliate links to monetize off the list.
As far as a monthly rent credit... I agree to keep it low on a $450.00 a month rent.... nothing more than $100.00 that's applied to the purchase price on the back end ONLY if they excercise their option to purchase. It never comes off the upfront rent money. Make sure to inform them that if they don't excercise their option to purchase the house, then they lose the option money and the rent credits because they are non-refundable.
Best regards,