How inexpensive are used VR headsets now?

I'd really like to get into VR via my PC but money is tighter than usual. I'm thinking with the holidays just happening, maybe people will be selling their old models or something.

What would you guys recommend looking for and what sort of prices should I expect? I mainly want it for games stuff like Beat Saber, and porn obviously, so as long as it works pretty well then I don't care if it's an older uncool model or whatever.

Thanks for any help!