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I cannot find definite and clear answer to coins question in Rivers of Catan. Can you buy coins at harbors or "bank"? Can you give 3 any resource for 1 coin at 3:1 harbour, 2 recources for 1 coin at 2:1 harbour, and 4 recources of any kind to bank for 1 coin?
If you can, it affects a lot poor/wealthiest settler aspect of this game.
I have played both ways, you can and you cannot buy coins. It was fun both ways. If we could buy coins, we could make the player with most VP the poorest settler just by buying a lot of coins.
I believe that the clearest answer is this one from Sebastian Rapp of Kosmos (the German publisher of Settlers).
Sebastian Rapp wrote:
Thanks for making me aware of this difference between (original) German and English rules.
This is how the rule should be:
1. You can buy resources for 2 gold twice each turn.
2. You can include gold into trades with other players in any way you like - that is, receive or give.
3. You cannot trade gold in any other way into resources!
4. You can trade resources into gold in the usual ways - that is, bank trade at 4:1 or 3:1 and 2:1 if applicable - but not vice versa.
In fact, even if it was allowed to trade gold into resources via bank trade, the best exchange rate would be 3:1, because there is no gold-harbor. But trading gold into resources 4:1 or 3:1 is not allowed.
So, the maximum you can do each turn is buy (up to) 2 resources for (up to) 4 gold.
This has also been checked with designer Klaus Teuber, Mayfair Games has been made aware of this rules error.
Sebastian Rapp / Kosmos