I can answer a few of these questions.Most states have "controlling interest" statutes which govern when a sale of a real estate entity triggers transfer and recordation taxes to become due, regardless of the fact that there is no deed recorded.

I've wanted to brrrr something as well in the future but if your numbers end up working out and it's a solid investment pull the trigger 

I am aware of the rules about an owner staying at their own rental property and that if they are staying there to perform maintenance / repairs that this does not count as a "personal" day, I don't want to trigger my property to be classified as a personal residence.

A lot of my clients aren't doing the level of rehab he is doing, but you do have to know the triggers in the construction process that lead to these big upgrades if you are working in these burbs.

This is an inexpensive way to cover any possible injury focused lawsuits.

In general, how many deals would you say you look at before pulling the trigger and getting an offer out?

I was toying with the idea of buying a rental property for several years before finally pulling the trigger last November.

What's working for you is the extraordinary appreciation even befe construction is complete and the fact that you are now uncomfortable with holding such an asset for investment use.So in your case it's going to come down to what you and your accountant believe you can demonstrate as a legitimate intent.  1031s are not an audit trigger but my rule is never do something just because you can get away with it. 

The numbers just made sense on a duplex, so I pulled the trigger.

Ask them to explain what "Personal Injury" coverage is and why it is important especially to Landlords.