I offered not to raise a rent and if they extend, they could cancel any time to buy their house.

The financing contingency period is up tomorrow and it looks like they are going to back out, so I guess we will put the property back on the market as a cash-only purchase and see what happens. 

Are there buyouts or bail periods negotiated and written before beginning.

Alternatively, if more time is needed, then they could pay you a fee to sell them an "option contract" to buy the property at a set price within a given time period.

They extended one loan a couple times and even gave me some more money. 

It has been in effect since early 2022, requiring licensing for STRs and max 180-day listing periods. 

Sometimes issues can go unnoticed and get much more expensive if you can’t see the property physically for long periods of time.  

If extending for a longer term I would simply write the longer term, particularly if you are adding different terms.

We've had to keep extending closing for weeks because his communication is almost non-existent.

I used to have several out of state investors who would buy houses in Memphis via the online tax sale auction, then hold them for a year so the redemption period ended, then they would hire an attorney to "quiet" the title which would take 4-6 months and cost roughly $5000 but then they had clear title and would sell it "as-is" to other investors or hire me and list it on the MLS and get higher offers.