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.

Start with BiggerPockets Ultimate Beginners Guide (free).

Ultimately, I would like to invest in more deals with a smaller number of sponsors as I see how their deals (that I have invested in) perform.

As a mental exercise, can you imagine the perspective of an investor that bought a property from you just 8 months prior to that email, had his FIRST TENANT miss payments, lie about making payments, make partial payments, then ultimately skip out on four months rent?

My ultimate goal is to acquire multifamily units.

After looking at the competition and the demand in the market we ultimately sold them to an out of state investor with seller financing.

Ultimately when it comes to using leverage it is about knowing your exit strategies.