Technically, you can purchase an extended license of a PSD , code it into something like a Joomla template, and then sell it on ThemeForest.
I’ll also remind you that we’re working on that collaboration feature – that will allow a designer and coder to work together on a project, and split the proceeds.
You cannot buy a PSD from here, code it, and then sell it here. However I do believe you are allowed to sell it elsewhere.
You can if you have permission from the author. I think they are mistaken though, as the way I do it is code author’s PSD templates and then split the profit 50/50, (and they upload the html file on their account).
But no, you cannot just buy a PSD , code it, and then sell it without asking for permission, otherwise their would be a billion of people trying to get away with this