The million dollar question to y'all is:
What would you like to see in your ideal gun shop?Now, please, don't say ammo. Yes, we all want to see ammo back on gun store shelves. Don't say barrels full of SKSs for $39 or M1 carbines for $60. While it would be great, Dennis's store is in Tennessee, not Disney's Fantasy land. He'll be getting in guns from manufacturers as they become available. Firearms and ammunition are subject to market forces - Dennis isn't going to have rows of KSGs available, or M4-type ARs for $550.
What he's looking for are suggestions on other items he might want to think about carrying. I jokingly suggested "beef jerky" when he originally told me his plan - every gun show I've been to, there's been at least one table selling beef jerky (real beef jerky, not the stuff in a plastic wrapper). He's thinking about it.
Obviously he'll have holsters and gun belts, but what else? Knives? Steel targets? Specific types of cleaning supplies (M-Pro7! Frog Lube!)? Something I haven't seen in any gun shop are firearms specific tools - yeah, most gun shops have a gunsmith or two working for them, but a set of brass punches and a sight pushing tool aren't going to make them starve.
With the internet/Amazon/Brownells as they are, pretty much everything you could ever want is available to you online. Personally, I think Dennis would be well-served to stock "impulse" items - spare magazines, basic cleaning supplies, targets, etc. Stuff that you would need if you wanted to get up and running right that day - as well as the kind of things you're going to want to see in person before purchasing (one of my suggestions was a line of cover garments...)
What are some of the things you'd like to see in your ideal gun store?
That is all.