Plugin Help Lightweight Quest Plugin

I'm not exactly sure where to put this, but this seemed like the right area: I need a lightweight quest plugin to use on my server. No, I don't need a completely new plugin, I just need a suggestion. I'm looking for a plugin that would allow for only completing a quest once, I just need a simple task; selling items. That's about it, if you have a plugin that allows to sell items only once and a reward, then that would be great. Thanks.