Wine shop. The little groceries that are everywhere often have a few casks in front or bottles with stickers on them inside. Bulgaria, we were told, was once the world's largest wine producer. Prices on the kegs are for a liter. One lev is worth about 60 U.S. cents, so prices range from about 80 cents per liter to $1.20.
Of course one of us tried the wine. Our tester demonstrated that it was all "drinkable" and pronounced some of it "very good."