Tee shirt businesses and clothing lines have several different "levels." For example, a Champion tee shirt vs. a Abercrombie tee shirt. There, you're looking at least a $40 difference in selling price. Now, take an Abercrombie tee shirt vs. an Ed Hardy tee shirt... there you would have a $30 difference in selling price. Finally, take an Ed Hardy tee shirt vs. a Gucci tee shirt... $200 jump in selling price. The point is, which market are you going to target?
The general population, Champion... maybe Abercrombie?
The middle to wealthy population, Abercrombie to Ed Hardy?
or
The Rich population, Gucci to Prada?
After you have that figured out, you can determine your competition. You may believe: It's going to take some startup money to compete with Champion. It's going to take more startup money to compete with Abercrombie. It's going to take even more startup money to compete with Ed Hardy. And it's going to take a whole lot of money to compete with Gucci. In some cases, this is true. However, much of your tee shirt business is going to depend on the next step...