I didn't rent to Person X because they weren't COVID vaccinated and it was a bigger financial risk to me.I didn't rent to Person X because they have cancer and it was a bigger financial risk to me.I didn't rent to Person X because they were pregnant and it was a bigger financial risk to me.Notice a pattern there with regards to making illegal decisions based on the medical condition of the renter? 

They lack self control and make financially unsound decisions.

At that point, you'll make good financial decisions. 

I also have a deadline looming (lease renewal is up soon and I have to make a decision to renew, OR change the lease to allow the ADU add-on or sale of the property).Any direction to useful calculators, articles to read or how to set-up a spreadsheet to give the appropriate analysis would be greatly appreciated.

Co-GP who would not have any voting rights or management decision authority.

I am good at research, poor on decision making.

While this is a business and it may be a sound business decision I feel like we are starting to set a precedent. 

Some people are stuck in their own routines and limitation and are unwilling to take on a new decision or responsibility. 

I've been told that a home warranty is a smart decision for landlording.

The only decision you can make is when to get in and when to get out.