Selling merch at events?

I would love to sell Serenity necklaces (that I make) at the next Boston CSTS event. I can afford to donate 50% to charity, but not the whole 100%. Is it allowed/desired to sell things at CSTS, and do they have to be completely for charity or can the profit be split with Equality Now? Thanks for your help; I'd really like to do this next year.

This is something you'd need to negotiate with the event organisers. Generally, where events have vendors, they usually charge a table fee plus expect that a portion of the sales go to the charities they have designated.