Wine/champagne
It’s not uncommon for restaurants to charge two or even three times retail for a bottle of wine. Order by the glass, and you’re sipping on an item marked up as much as 400 percent. So scan the menu for a reasonably priced bottle (tip: look for house wines). Some restaurants allow you to bring your own bottle, though they’ll usually charge a corkage fee, and it’s best to arrange it in advance. It’s pretty simple math to figure out which is cheaper.