Guaro mixed with Cafe Rica, a potent coffee liqueur akin to Mexican Kahlua. Avoid the local wines. The most memorable thing about them is the hangover. Imported wines are expensive with the exception of Chilean and Argentinian wines, of which there are some superb options. Costa Rica, you'll often hear, is a nation of drinkers.
Most nations are.
Still, drinking is not restricted to lunch and the evening hours. Don't be surprised to find the Tico at the table next to yours washing his breakfast down with whiskey.