My plan was to build and sell the beach house or have it on AirBnB. 

A landlord does not need to provide a reasonable accommodation for an emotional support animal when:The property is an owner-occupied building with four or fewer unitsThe property is a single-family home sold or rented by the owner without the use of an agentThe emotional support animal poses a risk to the health or safety of other people, or a risk of substantial damage to property (but this risk must be specific to the animal and cannot be based solely on assumptions about the animal’s breed)"Definitely have a chat with a local attorney to ensure your local laws apply, nonetheless since its an owner occupant, it sounds like you have some recourse to deny this request. 

In future if I decided to build and convert both lots to one apartment building should I convert 2 parcels to 1 parcel?

I'm ready to start building up my team for investing, we're starting out with TX and NC.

Now 3 years later I work with one of the tenants there and she reports significant 1”-2” cracks have developed in the walls throughout the building.

I was looking at an apartment building 100 units for 17 million with a 10 cap. 

Kudos to you for helping women get into the game and build wealth! 

I'm particularly passionate about building and expanding my real estate portfolio and partnering with likeminded investors. 

I am an engineer with a full time job, but plan on continuing to purchase rent ready properties to slowly build wealth.

If you go that route, you should and will, build a relationship over time.