Market Board Suggestion

[KisaiTenshi]

Just buy the stack use what you need and sell the rest. I have actually made a ton of extra gil doing this (depending on the item). Even if it sells at the same price you bought it for you'll get your money back.

This pretty much.

For most cheap materials that are undervalued, you can just buy the 99 stacks, use what you need, and then sell the small stack back on the market and have someone else buy it because they don't want 99 either.