Well well Dude! Let me know when you open, I'll be your first browser!
Anyway, here's my thoughts:
Find out if Isle of Wight or Franklin is even agreeable to zoning a gun shop. There used to be Kings on southern 258 and one on Main Street so I don't think they'd be against it.
This is not a heavily populated area so the chances for big money aren't too great unles you are truly unique.
A range would be a big plus but also bring regulatory issues. See Sussex County thread.
Accessories and guns may be cheaper on the internet but there's a lot to be said for hands on shopping. I enjoy going to the Carrollton gun shop just because they have a larger holster inventory than most gun shops, so I can test the product.
Be prepared for a lot of idiotic and/or first time buyers. Patience is a virtue with you and your employees. One of the biggest complaints I hear from customers is that they were treated rudely at a gun store and will never go back. When you get someone who is clueless about what they want, you must be knowledgeable, able to gently educate them without making them feel stupid, and able to refer them to training, etc. Above all don't be afraid to tell a customer you don't know the answer to a question, but you will get the answer for them. People are willing to forego the internet when they can get a friendly straight answer face to face.
On the other hand, be willing to transfer internet purchases. The customer will appreciate your demeanor and probably come back to you for their further needs. This is also an opportunity to sell ammo, etc.
Are you going to offer gunsmith services? CHP training? Shooting competition?
Inventory... I have heard that some manufacturers will float you inventory on credit but they often limit you to what kind of competitors you can retail.
There was a story in the NRA rag several years ago about a gun store in Los Angeles that took a whole new direction with their store as far as decor, accessories, friendly, range, etc. It was a million dollar store but they were swamped with customers. But then we're not in LA and don't have the same clientele. Out here it's going to be mostly economical self defense pistols and hunting long arms, and accessories.
Maybe have a few chairs and tables, coffee, whatever to encourage people to be in the store. Happy loiterers turn into buyers and scare off bad guys.
Don't overlook the female shooter. They are a growing business in gun sales.
Have an alarm and a safe. Lock your guns up every night. Consider roll down security doors. Harden all other doors and consider that a determined thief will breach a wall.
Do your research. Find gun owners and ask them what would bring them into a gun shop.
I'm sure there's lots more good advice out there. Good luck! And keep in touch, I'll be glad to help anyway I can.
