My sister asked me to let them do a presentation at my house. I didn't want to do it, but it would help her out. When Teresa came to my house and hit me with her sale pitch, I wasn't feeling any of it ...

In Bilyana Nikolova's grocery store in Chuprene, a village in northwestern Bulgaria, prices are now displayed in levs and euros on hundreds of food products and other items. Still, the shopkeeper, 53, ...