In Old School RuneScape, buy limits refer to the restrictions put in place on the amount of certain items that can be bought from the Grand Exchange every 4 hours.
These limits are intended to prevent market manipulation and ensure fair trading for all players. The buy limit for an item can vary depending on the item's popularity, rarity, and other factors. Once a player reaches the buy limit for a specific item, they will not be able to purchase any more of that item from the Grand Exchange for a certain period of time.
The specific buy limit for an item can be found below!
Highest buy price
Highest price * limit
Lowest buy price
Lowest price * limit