I also started letting others in the public know what I do,meat I have done, and what I had coming up, via my website, via Biggerpockets, via linkedin, and other so ail media avenues.

Just inspect everything carefully around the whole house and go ask the hardware store guy what products to use for each area you find gaps in. 

I think the risk with those is that your one tenant may go belly up (think about all the big box stores that no longer exist) and leave you holding a purpose built building that has little value.

We remove, de-lime/clean and store away.

I usually only purchase direct from an owner and not a store.

About how much does it cost, on average, to pay someone to help with SEO, site content, and tying this together with social media?

Verify they are real people on FB or other social media avenues.  

In this case you can try a FHA loan and go for a mixed use property which is a building that ,the first floor is for business related,rental office ,mini store etc..

My father owns a Nail Supply store and has not opened a Business line of credit.

Hardly anyone in mainstream media is talking about it which makes it even more interesting.