After spending way too much time on YJA and eBay, I eventually realized that YJA seller "barofever" has some of the same albums for sale that champs has.  Comparing a few items side-by-side shows that the two sellers' pictures are actually identical, which strongly suggests they're the same person.  A few examples of this are below.

I guess this means that if you're buying from champs, it might be worth seeing if barofever has the same item cheaper, as the prices aren't identical.

Panzer Dragon II Zwei

http://www.ebay.com/itm/Panzer-Dragoon- … Sw2gxYnvqs
https://ord.yahoo.co.jp/o/auction/RV=1/ … oAEQ.hGzx8

Athena the Music

http://www.ebay.com/itm/ATHENA-THE-MUSI … SwhQhY0i8r
https://ord.yahoo.co.jp/o/auction/RV=1/ … oAHQ.hGzx8

Ghost Trick

http://www.ebay.com/itm/GHOST-TRICK-Cap … Swls5Y74Nc
https://ord.yahoo.co.jp/o/auction/RV=1/ … oAOw.hGzx8

i read that name as barf-forever

Kind of off-topic, but add Ghost Trick to the list of albums I'm glad I bought cheap(ish) when I had the chance if those prices are what the thing is going for these days.

I had the chance to grab it for 4k yen and passed.  In theory if the price is there now I made a mistake, but I've never heard the music so it didn't necessarily jump out at me when I saw it two years ago.  Then again, at some point champ just started pricing all his stuff ridiculously so not sure how much stock I put in it...

To be honest I haven't bought anything off champs in a while; it use to be a somewhat regular occurrence.

I got some somewhat difficult to find albums through him, thankfully before the prices spiked. I'm looking at you Rockman DASH.

Well, back in the day on ebay (at least with the more common items) he would start everything at 99 cents.  This was great in that you could win obscure items at a reasonable cost so if it ended up not being good the loss wasn't too bad.  I feel like I haven't really experimented with soundtrack purchases in quite a while.