Charge a fee for the ESA.

I would also give her x amount of days to move but let her know you will have to charge a prorated fee per day after that to move for occupying both units. 

We are pet friendly and have some zeroscape backyards and have wording like "We are pet friendly with a fee, but please note although backyard is fenced there is no grass and certain areas contain crushed shell which could hurt your pets feet". 

Let’s say with your plan they make an extra $100 or $200 in fees and you lose $1000 or $2,000 in bookings.

Gaining a risk-free property, with a long-term resident there to pay down your fees, etc, with a property management company in place to hold your hand along the way and making sure your property is kept up with. 

It is also important to consider the transactional fees associated with originating the HELOC, whether an appraisal is required etc.

This requires consistent oversight and experience, which most investors simply don’t have.The Bottom LineIf you want to lose money and risk expensive legal fees, go ahead and self-manage.

Or would it be minus realty fees and closing costs as well?

The penalty can be reduced, but there's a fee (or you take a higher interest rate). 

There are sometimes fees associated as well but they seem minimal and scale well since one line of credit can purchase multiple assets.Interested if anyone else is using this lending strategy and what your experiences/recommendations are.