Originally Posted by
Paladinleeds
Funnily enough, RuneScape at least USED to do that with the Grand Exchange and trading. There were certain caps to value that could be traded. So you had to follow the markets when selling, you couldn't deviate too far. I believe on the Grand Exchange you were only allowed to deviate 5% from the average price (it'd adjust automatically dependent on how much an item was trading for, if the item was selling consistently above average, average price would go up, and vice-versa for if it was consistently selling below average). And trades outside of the GE had to have value of max 100k difference traded between both sides, and once you'd used that allowance it took time to recharge as well. I think it was 24 hours.