i bought a Yoshihiro yanagi from a source on eBay a couple years ago, and while it has ended up being a perfectly fine knife, it took a lot of work to get it there, because it was ground very inconsistently. i would buy from Jon, because you can be sure to get a nice knife from him.
I second JKI! Jon took a good amount of time to talk me through the various "brands", steels, etc when I was looking for a Suji. Jon knows what to look for in the knives, so it would be a no brainer to go thru Jon at JKI than roll the dice on the Ebay knife, especially if it's your first and you don't know how to fix the high/low spots and stuff.
Pay a bit more and get Gesshin Uraku by Yoshihiro from Jon, if you want a white #2 Yoshihiro yanagiba.
I've had one white #2 direct from ebay, and it came with a bad bevel grind towards the tip i.e. shinogi line
starts to bend back downward.