Has anyone worked with one of these businesses or something similar? 

However, the issue I have is that I only have 1 year of solid income from the business, the year prior to that is inadequate, and I know most mortgage companies require 2 years of income to qualify.

You have become an insurance company, only you didn't get a just premium.The potential of rent forfeiture is part of the business in reserving a vacation home, and everyone knows this going in.

Struggling on the best way to step in to this realm of business.

Many are too busy.4) "There are several properties in the area that have multiple homes on small acres" does NOT answer my previous question.

You need business insurance to cover your own negligence and liability.

What's the best business bank account and the best business credit card?

I’m in the FLL area and could be boots on the ground for out of state investors, could go by and take pictures/videos, visit municipalities, and the like to help with your business. 

My business partner has completed many projects under previous companies he formed until he sold them a while back.

Having a family there are always reasons why funds cannot be allocated towards starting a business or investments.