David,1) You (and any other "disqualified person") are not allowed to use property owned by your retirement account or receive any other benefit from the investment owned by your 401k.

I think the real benefit in having your license is networking and meeting people that can and will help you.

If you follow all the rules you will avoid any gain on the property you sold, remain invested in productive real estate, and receive the whatever tax benefits remain in owning a house after any tax reform is completed.This would entail many assumptions and an after tax cash flow analysis but I think the best and worse case scenarios would give you some comfort in making a decision. 

And that both properties are turn key with maybe some room to update over time.At first glance most would say go for the cash flow, but I was thinking about the benefits of the higher purchase price as well.

After listening to BP podcasts recently I realized I essentially did the BRRRR strategy without even knowing it.

Essentially, you get contractor bids and give it to the appraiser and the appraiser goes to the home and uses the bids to see how the home would look after. 

There are a few structuring options that may benefit you.

Although we only have duplexes at this time in our LLC, is there any benefit to putting his new home in the LLC and have a rental agreement with my father?  

I am not considering tax benefit and equity for simplicity.

Does any one have that form or something they use that essentially does that?