S&W or Ruger, used - maybe $300. Lots can be had for less than that, too.
Colt Python, used - been a long time since I've seen one under $700-800.
Is the Colt worth $400-500 more beans just for a home defense handgun?
You do the math.
I personally prefer a shorter-barreled gun for home defense for a couple of reasons:
1. Easier to maneuver into/out of a nightstand drawer or safe.
2. Less chance of it being used as a "handle" if you come in contact range with a bad guy.