I'm wanting a 223. I've always wanted one. All I plan on doing with it is a little yote hunting and letting my wife shoot it. I'm not wanting to sink alot of money into one. Is it possible to find a alright used one for under 400$

If you go with a Stevens or Howa you could purchase a new one for less than that. Either will shoot well enough for what you described and leave enough for decent optics.

Yep, you should be able to find a great used one for under $400. Look for a Rem 700.