First, build the actual business in theory with a brand.Second, go to every real estate investor meetup in the area and see if this is something that people would pay for and if so, how much.

If the deal is good enough you can find an investor to buy it without inspections. 

What are some good things to be looking for and thinking about for a prospective buyer who is walking the grounds of a 47 unit building?

This way you can learn what it takes to be a landlord, produce extra income that can be put towards your mortgage, and build equity.  

It would be installed in the middle of the porch, as circled in the below photo.Per my handyman, "All materials and labor to build deck section and install hot tub supplied by you including water, drain and electric hook up.

and will build appreciation and equity (via tenant paying your mortgage) until you sell.Selling in 2-3 years for 121 Tax Exclusion is probably best, though.Anything else will depend on your investment goals. 

suggest you start with Dave Ramsey principals ... then move out from there.there is some big huge fallacy  that Real estate is going to let you quit your job and your going to have all this time for the kiddos etc.this will never happen in the short term with rental property.. you build a nice base for retirement in 30 plus years for sure.. but for short term replace your income and have all this free time you need to make transactional income with big hits.. your not going to get their with 200 to 300 a month cash flow on a levered up rental . 

My latest misadventure in property management, a police car crashed into one of my buildings.

I agree with what you said in your post, maybe add management as you build your portfolio. 

Don't look for a handout, go build connections.Figure out what your why is.