We sold a property using the 1031 process and were approached by a business about purchasing a piece of commercial property for them with the intent to create a rent to own agreement.  

How do you approach this, and what specifically do you ask for in this regard?  

You can discover partners or investors/private lenders at your local real estate investor meetings.. or something more creative like attending an IRA educational seminar or class and approaching others who attend that are looking to invest more creatively into real estate.

I got my network in Kansas City from BEING in Kansas City.What do you think the best approach to building a team is?

We get him set up with a temporary Nevada specific program that was incredible, giving him 10% in free money due to the zip code the home was in.

The demand is incredible.

Has anyone approached building duplexes this way?  

My calendars stay VERY full using this approach. 

Other than this approach (and no selling financing/deferred sales trust) is there any other approach to defer tax on the sale of your primary residence when your taxable gain is over $500K?

But those will be >$500k and not sure if it would fit your model (although not sure I know the approach you are looking to take...are you looking to buy & hold, house hack, flip, wholesale?)