10-12 bucks tops, and that's without even looking at them. Most I ever paid for a tank top was 18, and that was quicksilver.... had a lot of screen print, big wave design from front to back.
To be honest, you might as well not even market here, your plan sucks. You really thought you would just bounce in here and sell shit? Sure spent 5 bucks tossing some logo on a tanktop and sell em to suckers for 22...
On the other hand, hang around for a year or so, contribute to the forums in some way, earn out respect, then maybe try to market something. Do some research around here, there is one retailer that gave away a shitload of boards for x-mas, another retailer that one of their reps takes his personal time to give gear advice, never pushes products but posts sale so we have a heads up.
Or do like most who want some quick dollars.....be a d-bag n jus dip yo!!