Again, I want you to be successful at what you want, but be honest with yourself about what your ultimate goal is: 1) cool vacation homes to own and stay at or 2) a cashflowing business.  

The ultimate test is what the market will bear.

Ultimately we decided to proceed with them and signed a 1 year lease as normal.

I spent a lot of time thinking about this and who the ideal tenant would be and ultimately decided long-term would be best.

By integrating CPAs into the initial discussions, real estate funds can be structured more effectively, with tax considerations and financial goals addressed comprehensively from the start, ultimately avoiding costly amendments and adjustments down the line.

Start with BiggerPockets Ultimate Beginners Guide (free).

It will be such an amazing achievement to reach financial freedom through cash flow—that is my ultimate goal as well! 

Ultimately, I'd like to have 3-5 paid for properties heading into retirement at 65.

While you can supply important information to the appraiser, such as recent improvements or distinguishing features, they must ultimately provide an impartial market valuation.

Here are a few I recommend: "Rich Dad, Poor Dad" by Roberto Kiyosaki; "Set for Life" by Scott Trench; "The Unofficial Guide to Real Estate Investing" by Spencer; "The BiggerPockets Ultimate Beginners Guide" found here on BP; "The Book on Rental Property Investing" by Brandon Tuner.