Let's talk store front.  

Own property next to a Dollar General Store and looking for a business/idea that would complement DG, attract their  client/customer base

People don't go to the grocery store or gas station and expect to get food and groceries for free because they're sick. 

I would like to keep using a cheap, larger format tile (so that we minimize grout lines) with dark colored grout, but need some fresh ideas to modernize it a bit. 

I realize that this may need some light fixing up here and there since it's not freshly rehabbed.

And if it's in both units you can buy a couple of extra boxes for the inevitable cracks and store them in your closet.  

I'm currently reading https://www.biggerpockets.com/store/long-distance-... and lots of good advice there.

I am in a position pretty similar to you, (freshly) 25, finished up college a little over a year ago, and looking at getting into this in the next 6 months and move to the Winchester, VA area.

Go to the BiggerPockets store category and read every book listed.

I liked the tenant he found and decided to just do a fresh lease with him.