We are in northern Ohio, so I figured that anyone wanting to store an RV would want something enclosed or at least with a roof, but several colleagues have said there is a strong market for just open parking.

@Brandon Turner has a book on no and low money down investing.It is available under the store tab above.

We give a greeting card with a $15 gift card to a local grocery store/merchandise store (Fred Meyer, which is a Kroger store).

More of a small "Thank You for your business" - thinking a $25 gift card for the local grocery store and a box of chocolates.  

Look around the town, are there a lot of empty store-fronts?

The college kids in this area even pay ahead for next year and over the summer to store their stuff.

If you're responsible with money - you should 100% look into Travel Hacking with credit cards.It's almost never worth getting "store" brand cards.

I pull them all the time in our business and I also pull them when I’m buying something off craigslist, ebay, or in a market / store where negotiation feels appropriate.Lever One.

Menards is moving out of their small location to build a much larger store which will add additional jobs to the area.

One of my clients had a cell phone store franchisee a national brand claim that rent was too high and would have to shut down business if not a concession by landlord.