image.jpgHow much are my items worth?

I have a sealed/boxed copy of DDR with Mario (Japanese) in the box. I paid $40 total on ebay. I've heard they're rare. North American ones are worth $100+ still in the box and they made 360,000 copies. They only made 100,000 Japanese copies. So does that make it more rare and valuable? NTSC versions are rare, and since few jap copies were made, does that mean more rarity?

Second, I have a sealed Intec Gamecube Sound System still in the box and plastic case thing. I paid $40. Is it rare and valuable being new?

Also, I have a sealed 2001 Gamecube Preview DVD. I paid $8 It's a DVD they had in stores at the time of the gamecube's release to promote game sales.

And sealed copy of Rockman EXE Transmission (Jap) paid $10 on eBay

Rarity?
Value?

The pic of the stuff is below


Thnx