Well in my opinion, the chances of you opening a coffee shop in 'dam are slim to none.

Just think how many people thought and are thinking the same thing, and if everyone managed to do it Amsterdam would be overflowing with coffee shops. I think the coffee shops that are there will have been there for a while, and new ones opening would be few and far between....but thats just what I think
I can imagine it would be one of the hardest businesses to open over there, you would have more chance opening a fish market or something.

This topic has been done quite a few times here, if you search im sure you would find more infomation