It's a nice-to-have in my eyes.I think what's more important is ensuring that there are proper incentives that reward those who are materially participating in the deal.

Below is a link that describes passive vs active vs material participation.

Here are highlights of the program right from their website:Program Benefits-A 30-year fixed interest rate mortgage loan, several rates and loan options available-Down payment assistance (DPA) 3% to 5% of the loan amount-You do not have to be a first-time homebuyer-DPA provided as a grant (never needs to be repaid) or 3-year deferred forgivable second lien loan-Available statewide through a network of participating lenders.

That negotiation with cost participation, or their funding of the project should begin with them.    

I know a reputable CPA who focuses on real estate and actively participates in REI himself. 

That is a win and is usually way higher than the old landlord rent.Once you show them data and allow them to be a participant, you are working together.

If they reject the offer, then I would play hard ball by enforcing every term of the lease and ensuring they participate in showings or face termination.

I did a simple Google search.Read this:What Is Material Participation?

As my avg rental period is <8 days, and I have <14 days personal use at the property and believe I can meet the material participation test, this should be a non-passive activity.Specific Questions on Material Participation:1) Do hours logged for material participation in 2022 include time prior to placing the property in service (i.e. first half of 2022)?

Practically what you will earn from participating in tax sale auctions is an interest rate of return.