I’m basically making an RPG game in roblox and I want it to have a specific spot to trade with players and it work through other server/place and also when I’m offline. I want it to be like Old School RuneScape’s grand exchange. Example : So if I want to buy an iron sword for 5 coins and there is someone selling it for 4 coins with another guy selling it for 3 coins, I’ll get my sword with a 2 coins refund and the guy who was selling it for 3 coins will get his 3 coins with the other dude not selling his sword. What do I need to do for this to work?