Have you spoken with a lawyer @Tyler Shew?

I'm not a lawyer, but I'm almost certain that there NEEDS to be a reason in order to be discriminated against, such as race, religion, sex, etc.Unfortunately for you there is no law that says what type of flooring a unit needs to have.

I am in Florida  I called a lawyer and he said to give her 15 day notice.

So if one partner wants to sell it would be just for the properties we own the two of us and would have no effect on the others.  

But if your lease doesn't require her to show the bills, I'm not sure how you can force her to.But with only three months left on the lease I don't know that it's worthwhile to fight about it, or certainly retaining a lawyer.

I'm assuming I would need a lawyer though?

This is not cost effective for a rental based on the fact that no investor knows how long they will hold. 

If you do not use a creative method you will need a experienced lawyer.

Reinvesting it has no effect on the tax.Reinvestment within that activity, such as if you have a rental and if you spend that 15k to repair the house, which is expense, you wash out your income. 

So I have put some thought into this trying to determine what our best path is.I suspect that most areas of San Diego City do not have enough STRs to significantly effect the RE price in those areas.