There are a ton of hustlers who scan books with Amazon app or other and ship them into Amazon to be sold for profit.

Car, regular clothes, clothes with company logos, computer gear, printing and shipping services.Then there are fees for your database CRM, business cards, Google Adwerx, Facebook/Instagram ads, yard signs (lots of vandals), professional photography, staging services, open house flyers and buffet, list goes on and on.

. - Get serious about shipping out the offenders.

I also have a dock where it can be kept.

Clothing, auto food, loading docks, security, cash managers, cleaning staff, security, customer service. 

If you want to be filthy rich with the same amount of investing capital you have then get the mindset that you are the boss in your company, the person responsible for making the right decisions, the captain of your ship and THE CAPTAIN IS NEVER WRONG and learn to not make decisions on-the-fly and don't make decisions base on nobody who gives you advice.

When buying from Amazon, you can ship to Amazon lock box, which is at most 7'11.

We live in CO and own a vacation rental condo in Kihei, Maui and will use our experiences to answer your questions.1)  The only negatives about owning a VR in Hawaii are the higher costs of goods (furniture, building materials, etc...since everything has to be shipped in).  

(Ex: Having a dock in my area is a large expense that doesn't translate to much more revenue).Hope some of this helps.

However the first home of any kind I ever knew was constructed of bushes, dried tree branches, card board boxes, and everything tied together with shipping string, had dirt floors, no plumbing, no electricity, and not water.