If you say it's because it's of some legal infraction then why have you chosen that one rather than others (e.g adulterers are criminalized in many states why not them). 

Letting your in-laws take two years to get fully acquainted with their chosen retirement location while keeping their former primary residence let's them change their mind if the retirement location is not meeting their expectations.On the other hand, if after two years, the in-laws have settled into their retirement lifestyle and want to stay permanently, then they can sell the former primary residence and use the sale proceeds to buy their new retirement home while still keeping their capital gains exclusion on the sale of a primary residence intact..  

It likely contains verbiage to the effect of: "The Seller herein acknowledges that it is the intention of the Buyer to effect an IRS Section 1031 Tax-Deferred Exchange and that the Buyer's rights under this agreement shall be assigned to [insert name of Seller's chosen intermediary here] to facilitate such exchange.

It's difficult to learn through so many set backs but I'm glad you've chosen to share the experience with us.

I took the gains and some principal from the sales and invested in various syndications - chosen for the quality of the operator. 

If corporation status is chosen, the default is C-corp unless you make a separate election to be treated as an S-corp.

We have tentatively chosen Dallas-area as our first market to dive into as it seems to qualify for the signs of a healthy market (population growth, business/landlord friendly, etc). 

Memphis is a great cash flow town and you have chosen your turnkey provider well.

I am so inspired by the young folks on biggerpockets who have chosen to go “all in” so early in their lives.

You've chosen a very wise path!