For some reason, some japanese sellers just randomly put their items on discount.

Here's the price of each item when I got them and all them are brand new and sealed:

1/7 Amiya Deluxe Edition HobbyMax - $90.00 1/8 Kouka Beatless GSC - $73.00 Lucia PGR Ribose - $25.00 Full Mechanics Mailes Kenbu - $21.00 Chogokin Aerial - $75.00 (no picture yet, it's still being shipped).