When people say they sell or buy an item for x Tibia coins what does this mean?

Question

1. Does it mean you actually have to gift them tibia coins (this seems like you'd get scammed easily)?
2. Average value of Tibia coins in the market right now?
3. The buy or sell price of Tibia coins? 

Sorry, I was looking through advertising and noticed some people weren't referring to gold but rather tibia coins. I tried to ask a player what it meant but he was logged off. 

Answer 1

Usually they use tibia coins as price when buying or selling rare items or unique items (crown, etc) I only saw this type of stuff in streams so... yes people gift the coins to the other player and mostly it’s used because of price of coins in real life (because the tibia coins can change price from server to server)