Since LLCs don't do much (perhaps some wealth transfer within the OA or rules of the road with multiple members), they might not be worth it in high-fee states such as CA, MA and others.

What @John Underwood said, @Usman Khan.See what you can get the owners to do and transfer the LLC.

After the transfer happens.

In DeCleene, 115 T.C. 457 (2000) the taxpayer closed on a vacant lot and then transferred the lot to a third-party while improvements were constructed.

If you have a loan, you may wish to look into due-on-transfer clauses.

That's my understanding of Prop 19 and that passed under the guise of helping fire victims and senior citizens transfer their low property tax basis to a new property if they moved. 

I know 5 will not work as they don’t have the feature to defer capital gains that are invested in opportunity zone, so I will have to somehow manually record that in 8949 and transfer to Schedule D.After this is over, I will apply for a CPA license - I am now wondering if it is as easy as getting a license for property manger or real estate agent 😉

Other option would be subject to where the mortgage doesn't actually transfer into your name but you make the payments.

If you have it in writing that they left, double check all utilities are paid for and transfer them to your name. 

Well first one fails and of course they have transferred title or recorded the lease option.