You can have a bullet proof lease in place, but the best defense is good tenant screening on the front end. 

But still, ignorance isn’t a good legal defense.

@Marcus JohnsonYour right I never saw it that way and I am learning that I have ignored some responsibility or defensive actions to prevent late payments.

I really like what Brandon and David Greene talk about on the podcast which is that cash flow is defense and appreciation is offense.

With the kind of equity you'll have coming out it's also not a bad time to be looking at some defensive investing and allocating your proceeds strategically to lessen your correction exposure. 

Even if you don't end up accepting her as a tenant make sure there is a defensible reason besides age because I'm pretty sure its against discrimination laws.

However, if Austin becomes the new epicenter of American Corona virus during SXSW next month, that would break through our economic defenses. 

Your CPA is always your first line of defense. 

Most people are on defense right now and playing be ear.

If this is a small slice of property that hasn't been used by the claimant or his predecessors for 30 years, then a lawsuit against you is unlikely.But if you are sued, then based on what you've posted, you have a valid (legally cognizable) defense.  30 years of continuous use of the property by you and your predecessors constitutes (Adverse Possession and/or Prescriptive Easement).