Look at real estate professional status closely, this area of the tax code(section 469) is where I think If you worked with the right real estate-focused accountant you could save 100s of thousands of dollars. 

Things I’m thinking about is capital gains on sale, avoiding high property tax on duplex b/c the ones that are available are new builds.

Do you dislike your current property or think you could do better with a different investment?

Read your insurance policy before making a claim as I think most do not cover long-term damage especially if it could be easily found and mitigated.

Think of everything.

If a lender saves you $200/month on the payment but you spend an extra $8k in fees, you didn't get the terms you think.

I think this is different. 

Most of them think practically because the law is the law.

If a single deal works out at this scale, the family has problems like estate tax transfer limits ($13M per child) to think through.Further, as long as the funds/deals are separate from one another, the one that does go well instantly makes the syndicator an "expert" in that specific strategy or market, which then attracts the next 500K social media followers. 

Far too many get stuck in the "paralysis by analysis" stage, thinking they just don't know enough to get started.