Buying used is harder, it requires a lot more work/research (and a little bit of luck never hurts), than just trotting down to the RV sales lot and picking one out.... but it is worth it! I spent hours every day on line for weeks researching the purchase of our C. With the internet you can literally search every unit available from coast to coast. We looked at dozens of C's, essentially eliminating the junk from the higher end units. When the right one came along we knew and jumped all over it.
The advantages of buying used( and I'm talking 1 to 3 years old, lightly used and well maintained), are numerous, to name just a few:
Someone else takes the big depreciation hit.
Anything major will have been dealt with or will be glaringly apparent and the minor stuff has usually been fixed as well.
Most new warranties are of limited value and no better than the local dealer who may or may not stand behind it (stroll through this forum for numerous warranty nightmares).
You can get a much higher quality rig for far less money than the low end new coaches.
If you buy from a private party in some states (Arizona for one), there is no sales tax.
That first scratch or ding you put on it just doesn't hurt all that much. :B
Our 2012 Nexus Phantom 23P had 6,205 miles on it (2,000 of which were rolled up getting it from Elkhart IN to Tucson), 8.8 hours on the generator and was in "As new" condition throughout. We have now put 8,000+ miles on it in the last 4 months with zero (zip, nada, none whatsoever), issues. It was almost $20,000 less than a comparable new model and we ended up with one of the highest quality C's available. Were we extremely lucky? You betcha, but having done my homework paid off handsomely.
as always.... Opinions and YMMV. :C