To mitigate this we manage our cash reserves closely and I believe having cash on hand also buys you peace of mind along with flexibility.Best of luck

This leaves the retirement account owner to invest mostly within the plan (self directing) or to withdraw the funds to invest outside the plan.If you have a good accounting professional at your side, there are ways to use REI purchases to help offset your 401k/IRA/retirement plan withdrawals thereby creating a "wash," so strategies like this can mitigate your tax impact.I've worked on different cases where we've done rollovers from pre-tax to roth plans/withdraw while mitigating the tax impact of getting the funds out.Lenders are for the most part still behind the times when it comes to self directed accounts.

In addition, even though you would have no financing in your model you can mitigate the risk with proper cash reserves and grow 4 times as fast. 

Real estate has risk, but mitigate that risk in every way possible!

Would the drainage requirements be mitigated by making the parking lot from pervious pavement/asphalt and the installation of a green roof(which would contribute to stormwater absorption?)

While it is true that she signed a legally binding agreement, you have a legal responsibility to mitigate your losses.

If you brrrr you can probably scale very fast after you have a few under your belt and the experience to mitigate mistakes. 

As a novice investor, I’d like to mitigate risk as much as possible.My questions; Is the RE market cooling down?

It's those maniacs that buy homes cash via quit claim deed off of craigslist that really get screwed.Make sure your property manager is a licensed real estate brokerage.Understand you can not eliminate all risk, only mitigate it.

If you purchased right from the beginning then this risk should be mitigated.