1) There is a photography category in the contests.
2) you can't "officially' sell your entries at Joecon, as they are usually on display through the whole con. however, people can, and will contact YOU about buying your entries.
3) there is room to room trading and buying, as well as a buy/ sell/ trade board up for people to tack what they have.
4) There are a robust amount of Sellers and dealers there. The majority of them will have primarily Joe stuff (con rules), but some will have pretty much anything and everything.
however the majority of stuff will be Joes, or other 1:18 or 12 inch figures and vehicles.
as for bringing your parts. I wouldn't bother with the hassle. however, i WOULD take pictures of all the parts you have in the bin, and post it on the trade board for future trades.
then again, I f you wish to, you may get lucky with some of the vendors. Although I know a few vendors who do buy that stuff wont be attending.
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