I'm am thinking of a game concept and i was curious what your opinion is.
The concept is like this, its still very basic:
You got islands and every island produces products if you build a harbor you can receive goods from another island to the island with your harbor to transport goods you must use a harbor wich is specialized in that good, like you want to transport grane then there must be a harbor wich transport grane on the island where the grane is produced. The specialized harbors may be used by anyone and have to be build by one player. Your need your on harbor to receive goods if anybody else want to use it he has to pay a fee. If you ship goods you may only ship once at a turn. only to one harbor from one island. The goods wich are shipped to another island are then sold at the highest price everybody on that island may do a bid, including yourself.
Is this a concept wich is used before?
There are 2 games on computer which are VERY OLD which come to mind that I can think of with a similiarity to your concept.
Tai Pan which is a ship pirate game and you exchange goods as well increase your fleet and size of ship.
The second is "Gazillionaire" which is space based but doing a product transfer from one planet to another as well as patrons to travel onboard to achieve a set cash amount for winning the game. You buy product at one planet sell at another with a supply and demand button for each planet wanting different items kind of a market of commodities idea. You buy property to station increase warehouse space buy a bigger ship pay taxes, employees, and buy bigger engines for your ship to travel faster and the first to 1 million wins.