With the Amazon fulfillment center being built they are expected to keep on rising.

I like to draw up worst case, best case, and "muted good" (think inflation rate growth, normal expenses, etc.) case scenarios and see what your personal situation looks like in all three.I don't think you can "manage risk," everything you do has some associated risk and it is what it is - you can't change it.

I've contracted with an architect to design the prefabricated/modular high rise, and will have it overlooked by a team of civil engineers.My next steps would be to submit the proposals to city officials/zoning.

That is a great strategy, because they are actually investing the difference, instead of inflating their comfort of living.  

Assuming that oil prices are going to rise again and the demand and pricing for housing will increase, would it make sense to buy, flip, sell, etc. on mobile homes in a park or mobile homes with land?

Seemly appreciation historical rises in large cities with inflation and high demand.  

It sounds like the owners are just fishing for the a once in a lifetime buyer at an inflated price.

My friend is constantly telling me about the rising home prices and rapid gentrification in Seminole Heights.

I've noticed that prices rise before you even start seeing the changes.

But my feeling is that the banks will leave it alone for now, but when rates rise and a mortgage 10 years from now is 8% rather than 5% they will be motivated to start calling all these notes and forcing refinances at the higher rates.