I will return to this situation in the end of this post, but first let me show you why the age of a person can be tricky when it comes to the IRS.

My question is: could the current tenant (age 59) remain in the property if she becomes eligible for Section 8 assistance?

What a tremendous accomplishment at such a young age. 

Hey @Heather McNicol, we aren't anti-mentor.

Furthermore, California has a very anti-landlord and anti-real estate investor government that can cause you all sorts of other problems as well. 

Short-term rentals are becoming oversaturated in certain markets plus anti-STR legislation is resulting in some of those properties also converting to long-term rentals.You already have the operations experience by self-managing.

What they said.....everyone over the age of 18 has to have a background/credit/ ID verification and sign the lease.

In person is better than over the phone if possible, as I have been told by annoyed or lazy clerks "NO STR allowed" as that was the easy button to get me off the phone, or if they are anti STR. 

Congrats on your maturity at a such a young age.   

@Polat CaglayanI've never seen a formula but here is a general rule of thumb for multifamily:The class of an apartment refers to the quality of the building, which can be determined by a number of factors, including age, location, and condition: Class A: These are the highest quality apartments, typically built within the last 15 years.