I'd start getting addendums over to the seller extending escrow if that is the route you choose to go down, and learn the process for wherever you are so you can better estimate what to do with your current residence (probably take it off the market temporarily).

I think his tenants are people that want to live off base that usually lives in a nearby extended stay type of residence.

In this case, we actually had to extend closing twice due to loan underwriting.

In this case, we actually had to extend closing twice due to loan underwriting.

If we do extend their seller lease back, it will be on a new agreement with a minimum of 2 months and monthly extensions after that.

Phasing things out will extend the project and likely lower your IRR, but it also makes it easier to do in chunks potentially with fewer equity investors such that your stake could possibly be higher.  

Should Escrow fail to close in a timely manner through no fault ofBUYER, SELLER shall promptly remit to Escrow all funds received by SELLER and shall order all Depositsremitted by BUYER to SELLER or Escrow, to be refunded to BUYER within fifteen (15) days after the estimatedclosing date specified in this Purchase Agreement, or any mutually agreed upon extended closing date."

The four primary levers (or beneficial aspects) of real estate investing are:CashflowTax benefitsAppreciation EquityYou could start 2 decades from now and still benefit greatly from REI (primarily through Cashflow and Tax Benefits), but your potentially extended horizon means you will participate in each of these areas. 

I had suffered from some of the stress/health problems you spoke of and leaving the stressful environment has dramatically helped me. 

The across the grid uniform adjustment (averaging 24% of the sales prices) significantly reduces the reliability of the analysis.”Lender was going to send another appraiser to the property but seller did not want to extend the contract again (we had a few other delays already) so I lost the property.