Buy new if you can't do your own wrenching, I run a metric cruiser forum and you can find lots n lots of good deal n low mile bikes because they can't wrench and the shops milks em dry and get no where fast.
If you can wrench look for those low mile bikes that sat in a garage with gas in the tank for several years, which equaly gummed up carbs n such, but means a ubar low price. Then find a forum to get help fixing those minor things that gum up a bike from sitting.
Pretty much all my forum is for, helping folks help themself, they pick up a bike with low miles that wont run, they spend nearly as much in a shop as they did on the bike and it still wont run for crap, and then we talk them through DIY fixes that work the first time.
Bigger problem is most shop just don't care enough to open a book or look for help online. They know it all but I wouldn't have the #1 Yamaha Virago site if they knew what they were doing