The only reason I could see paying more to principal is if you didn't have 20% down and you were trying to get to a point where they would remove PMI from your payment, thereby improving your monthly cash flows.  

But with buying out the neighbors , road improvements , stormwater ponds , water discharge easements he is looking at another $250,000 on the low side , BEFORE he digs a foundation .  

As an opportunity to improve and learn from my mistakes.

I have seen rehabbers increase the value of a property by $100K by making $50K of improvements.

After a year or two of some improving I want to refinance and hopefully buy my second property.

When the market improved I sold it to my renters at a discount and it worked out pretty well for everyone.  

Just explain that you want to learn & improve your processes & are looking for feedback to better serve your customers.  

I'm considering at a place that wouldn't need "rehab" but would need some improvement in amenities which wouldn't really help the refinance part but change the cash flow by a lot.

If you're looking to use the funds for rehab/improvements, then you should definitely look at a renovation loan, namely the Homestyle program.

I should be taking my home improvement license exam before the spring.While looking at Baltimore, it seems to me that there is not yet a unified push to redevelop some of the rough areas.