Only 100k for all your work barely sounds worth it, with all respect. 

This would be done just to simplify operations, as currently the funds all have to be kept separate which means my employees have to use different credit cards etc for the personal properties, and they often mix them up which creates a huge headache.Concern there would be for material participation, as it might make the properties look passively managed to the IRS since they're being run through a management company (even though the management company is me).

Unless you've done complex tax preparation before ... hire someone.The CPA my clients in Colorado use for their Colorado STRs can usually get more in bonus depreciation with their cost segregation anyway, and like others have said, you want to make sure it's done right to defend in case anyone asks.Plus, it's nice to have a consultant who can walk you through what it takes to qualify for "material participation" as a short-term rental professional. 

Any tips on tracking hours and proving material participation?

And $5,000 poorer.Over the course of our relationship, we barely used 10 hours of their time, including the onboarding, the meetings and email communication.

For the first 6 years I owned rentals I barely got by out my self bookkeeping.

But even when I move out, I will barely cash flow after expenses, and i'm so okay with that.

I participated in 3 syndication deals total investment around $250K.

You will need to materially participate but it might help offset your tax issue.If the investment itself doesn’t pencil outside of the tax play, it may not be worth the added complexity, especially if you’re tying up cash and taking on debt for a relatively small offset.

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