Since most of the high end restaurants tend to be competitive on price, I'd suggest you check out their individual menus to offer some idea of the prices of the dishes you may want to order, since there is a decent gap between the lower priced meals and higher priced ones. Pick one of the restaurants--Bistrot Caraibbes, L' Auberge Gourmand, Le Cottage, L' Estaminet, et. al. for a general idea.
House wine tends to run 7-9 Euros a glass, but I have no idea what cocktails go for.
I'd say $100 is a minimum for a light appetite, and $150-175 is about what we spend, on average, for a more extensive meal--more if you have more that 1 bottle of wine, or better taste than I in wine.
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