Most of the answers here are correct and have value. But to put it simple, your price is always connected with your cost + margin. And it's just a math problem that you have to follow.
Don't look at market prices to define your prices without understand how much it costs you first. Think like a manager not like a consumer:
- How much it costs you to produce your product (materials, machines, electricity, etc)
- How much time it takes you to make X of your product. Give a price to that time (another formula).
- Add a margin to that. 10% ? 20%? 30%?
Now you have the fair price for you. It's time to look at the market and see how is your product price positioned regarding others. Too high ? It's time to reverse engineer and see where you can low your costs: Material ? Time to produce? Your Margin ?
Remember, you can always target your product to specific audience niches too, instead of general public. People that are willing to pay more for features that your product may have that others don't.
But then you also have to consider Marketing costs :).
Overall, don't sell yourself short because of what you see in Wallmart. If you define your price by competitors price, but your costs are higher, you may find yourself in trouble very soon. And then don't understand why are you selling so much, but still can't pay the bills :).
Hope it helps ;). Have a great week.