The Greater Phx area also has more places to expand, but be cautious of "island" developments that are separated from bigger cities. 

Out of these areas, Franklinton and Linden are seeing some of the most developments.

My CPA isn't well versed in 1031 exchanges and I want to know the effect of transferring title back to our names from a tax perspective. 

The biggest hurdle I see with arbitrage is developing a pitch to use when approaching landlords, which you can probably do with a little research on BP and ChatGPT.

Less Desirable Areas: Are there neighborhoods we should avoid or areas where BRRRR might be less effective?

I am considering working with a property developer in NJ to buy land, build a duplex/triplex and sell it (6-9 month time horizon).  

Literally your title is "business development" and you are saying that you "not here to sell you ANYTHING?"  

If it's more complicated eviction.com may be your best bet to use they are pretty cost effective.

Not to mention the economic development steps the town is taking in ensuring the growth of town (roads, schools, zoning) stays on par with the future expected population growth and new jobs that are going to be a result of the new factories opening.  

you have to learn land entitlement. we identified a site today for hotel development that was an 18000 sq ft lot.