Or, are there any tax consequences regarding the timing of the purchase, or the funds going through an intermediary, or the release of the boot relative to changing residency that I am unaware of?  

But, unless you are doing original investment research by yourself, managing the money yourself, writing the legal contracts to buy into a company yourself, not using any financial intermediaries, not using trust accounts (which eliminates all IRAs), you're not really doing it yourself. 

I'm actually a Qualified Intermediary for 1031 exchanges, and get questions like this all the time.

After day 45 this list is set and only the properties on it may be used for your exchange.Your intermediary simply needs to be in place anytime prior to the sale.  

Confirm that we can use the usual offer-to-purchase contract, but with “subject to" existing financing specifiedCan we use the attorney / escrow as an intermediary for the payments, to protect the seller?

The best thing you can do is make sure you have a team of superstars - an awesome agent who understands what you are trying to do and a qualified intermediary that has an incredible track record - I know several if you need a reference. 

This is where a CPA and your Qualified Intermediary comes in.

I sold a single family home in June, transferred all gains into a 1031 intermediary, and closed on the first duplex without issue (I used half the gains from the sale as a down payment).The second duplex was never formally under contract as the seller agreed to make some costly repairs so that purchase was delayed.

Perhaps I'm not asking it right because I'm getting looping answers between my lawyer/CPA/intermediary.  

This, combined with relative opacity -- the loans are negotiated in private or purchased through intermediary platforms -- mean there is more room for abuse of fiduciary duties to investors, market analysts said.