Just wondering if there are enough workers and companies to support the business and real estate in general.

But, you can do that in every other business. 

Make your bank stand out by ensuring FAST same day loan processing with better terms.If I owned BiggerPockets I would act on this IMMEDIATELY because it’s all about speed and execution in business. 

without having much demand from nurses, how this MTR business is doing for investors? 

And then there is leakage and failure.

The best thing for a system in failure is to pump the tank right away and let it sit.

I take the "its a business" idea a little differently.

I am selling my business and will soon have $850k cash on hand.

Sure it's not quick but building a business is not a quick way to wealth.

As for sources, in my area, there are businesses who specialize is refurbished items or surplus supplies.