Yes, this is purposely vague as there is not a one-size-fits-all answer here.

That means for tax purposes it’s as if they didn’t exist.

As for the eviction purpose, even if it's in your lease (eviction for illegal activites), you'll need to prove "the seriousness" (couple criteria) of the problem and give him notice to correct his behavior. 

Maybe that is on purpose (Maybe you want that to be less prominent)?

The key for my purposes is that if crafted correctly they do indeed provide an alternative to actual real estate ownership that qualifies for a 1031 exchange.  

Would you have advise on how I could calculate the hold cost for tax purposes?

Am I still able to consider my primary residence as a home office for purposes of mileage deduction to and from my rental properties and any errands involved in the business?

The Premises shall be used and occupied by Tenant and Tenant's immediate family, consisting of ______________________ __________________________ ____________, exclusively, as a private single family dwelling, and no part of the Premises shall be used at any time during the term of this Agreement by Tenant for the purpose of carrying on any business, profession, or trade of any kind, or for any purpose other than as a private single family dwelling.

You would have to sell it and then repurchase it again as the 401k rules don't yet recognize crypto to be used for contribution purposes like cash. 

For purposes of this subparagraph, in the case of an S corporation, an allocable share shall be the share holder’s pro rata share of an item.