How does the middleman (investor) exit out of the sandwich lease option once the investor finds an end buyer to close on the original purchase price between investor and seller?

High taxes.

Look to high-growth markets that stand to benefit from Bessent’s plans, especially areas tied to increased oil production or infrastructure expansion.

At the end of the day if you run your numbers and analyze like 10 properties a day, and every single day scour the internet for anything new, you will eventually find something that works and know it almost immediately.

Highly recommend (I require) collecting first month's rent prior to handing over keys.

At the end of the day, they're usually buying the products from the same outlets that you can!

At the end of the education, we'll you'll have an education. 

But presuming you are talking about doing the above, this is a high risk strategy.

Rental arbitrage isn’t common in my area ( high point North Carolina) but I was planning on starting in another state.

Tenants fool with you and they will end up in the Barrio.. in my court house steps days these were not tenants these were very pissed off homeowners who just lost thier home.. completely different their credit is already trashed etc..