I purchased my first property because I wanted to create another source of income  other than my W2.

Rentometer is alright if you're looking at the outer ends of the spectrum, but they aren't terribly accurate in judging the median.A solid option is to call up property management companies operating in an area and pick their brains.When we're determining median rent for apartments, we'll often call up similar properties in the surrounding area to schedule tours and determine baseline.If you know somebody with access to Costar, that can be a good source as well.

I own a 20-unit complex which is managed by Appfolio, so it distributes the vacancy to various sources.

Source: Fox19NowNews

I'm in a unique situation (like most) and have began seriously considering real estate investing as revenue source for my family.

I'd also become an absolute savage with saving as much as you possibly can from your primary income source.  

Governments will look for other sources of income = taxes in other areas. 

What is your source for this info?

Airbnb has been a great source of income for me but for the time being, I've transitioned to monthly rentals at least for the summer and have tenants moving in on Thursday.

An investment, if done properly, is an income generating asset that will grow your wealth.As far as choosing a market, Destin/30A/PCB is a tourism and STR hot spot, so there is data from several sources that you can use to estimate what you should be able to bring in on an annual basis.