There is always something in those areas that ''everybody needs'', but isn't available on the market. What related widget do you wish you had, but you can't buy? If you think that you need it, then 10,000 other enthusiasts also need it.
We sell a truck camper related product to solve a problem that exists with all campers, and that the camper manufactures won't provide. It's taken about 4 years from concept to full on production, but we can't keep up with the orders. And I might add, there was a lot of CAD work involved.