Itemshops are found in both Bavelock and Savina. Grace holds the itemshop in Bavelock, and Felix sells the same items in the Marketplace in Savina. In both shops you can buy the following items:

Potions
Replenishes 90 health points. They are sold for 20 Pix and bought for 10 Pix.

Elixirs
Replenishes 60 mana. They are sold for 20 Pix and bought for 15 Pix.

Ethers
Replenishes your energy in battle. They are sold for 25 Pix and bought for 20 Pix.

Remedies
Heals you from any status ailments in battle. They are sold for 25 Pix and bought for 20 Pix.

Limit Boosts
Completely fills your Limit bar in battle. They are sold for 40 Pix and bought for 30 Pix.

Empty Bottles
Used to concoct potions. They are sold for 3 Pix and bought for 1 Pix.