[hcv123]

I also owned a business (food) for almost 30 years. It is a matter of planning carefully, executing your plan and having a plan B if plan A doesn't work!

1) The 3 most important decisions in opening a retail business - as David shared - location, location and location. I would get demographic information on the shop he offered as well as trying to track down other successful B&M stores and ask them as well. I know in the food business there were pretty specific demographic targets that we looked for. I'm not sure if that type of data is purchasable somewhere (it was for food), but that would be mission critical!! If the "right" clientele isn't within a certain radius of your shop, that would be a virtually insurmountable problem.
2) Read the book "E-Myth Revisited" by Michael Kaplan. It is about the business of business.
3) Go in with a plan, plan to work and work the plan. If you fail to plan, you plan to fail.
4) Create a pro forma operating income statement - include all the variable and fixed costs you can thnk of: Rent, property taxes, CAM (common area maintenance), Electric, Gas, Water, Liability and property insurance, marketing and advertising, costs of supplies, bags, if you are going to have employees (payroll and payroll taxes), etc. - When you are done listing everything you can think of with their approximate monthly amounts add 20% for anything you might have missed. Once you have that number - that is the amount of profit (NOT sales, but profit) you will have to make to breakeven - anything above that, then you start making $$. Then you can start calculating how much you need to do in sales to cover that nut and get to profitability. After all of that , then you can start thinking about your product mix and gross profit per item to get there. Be more cautious/pessimistic in your planning and estimating. If things turn out better than you planned, that's an "easy" problem compared to if they turn out worse.
5) Owning your own business can be a lot of fun (in addition to a lot of work). A good friend and fellow business owner jokes frequently - "yeah, it's great! You get to decide which 80 hours a week you are going to work!"
6) It is not a decision I would make quickly or lightly. Have a clear grasp on the undertaking and time and $$ investment. Do your due diligence, reach out to existing or former collectibles owners (around the country away from you) about their positive and negative experiences - let them know you are thinking about opening a shop near you.
7) If you choose to move forward decide what part of the plan, shows, Ebay, Facebook, Instagram, etc. will be.

Hope that helps and best of luck whatever you ultimately decide.

Howard