I realize that the site says "In the future, we will expand in adjacent markets like multifamily acquisition and renovation, and non-bank new construction, which will greatly expand the market size addressed by Groundfloor."

Proximity to jobs is the #1 reason that people live in this area, and will continue to do so for the foreseeable future. 

I will reserve my opinion on your future.

We are predicted to have strong future increases in population.

Build it on excel is the best bet... you can adjust it for use in the future

If you want safer investments, you give up a greater potential reward.Betting on appreciation in the future is a lot riskier than analyzing current cash flow and making an investment based on that, but it could end up with a much greater return as your family friend noticed.It all comes down to what is your risk tolerance, and what are your goals.

But as far as future capital gains, the appraisal value would be my basis?

Well, Future welcome to you Ms.

Another assumption would be that I already have a couple investment properties that are cash flowing well to give me some extra income for future purchases and that I am 24 years old with my whole life ahead of me.

Just my advice that I think could protect all of you in the future.