We have a factory unit but it doesn't really do much good, minimal air flow. So I personally wouldn't put any effort into installing one. I find a table oscillating fan more effective and use it more than the ceiling fan.
I have an open area near a 12V ceiling light that is not attached to a wall switch. Though about putting it there. Seems like it's not a popular option, so, probably won't proceed. Thanks for everyone's input!