Speaking in a general sense I am planning on offering merch for sale to remember my panel (may not happen, so don't quote me on that as I have yet to finalize a design that I like). When the design is finalized, I plan on selling them at each convention AT COST. Any profit that is earned will be split between the vendor that I am selling the shirt with and the artist involved with the graphic work. At no time will any money touch my hands as the panelist outside of sending the money where it needs to go.

I'm asking because I honestly don't know, but what are some policies that you have run into as a panelist when dealing with merch? And am I even allowed to mention it in the panel itself?