No doubt that while you are in Havana you’ll be approached on the street by men and women who want to sell you “authentic” Cuban cigars. While the prices may be attractive and the cigars may look legit, you could have trouble at customs when you return to the United States, since the cigars won’t be packaged properly and will lack an official seal. If you’d rather not risk seizure, purchase your tobacco near the capitol building at Fábrica de Tabaco Partagás, one of Cuba's oldest cigar factories. Note that while you can buy cigars at the end of the Partagás tour (which is in a different location), they are cut-rate ones that are not packaged in official, sealed boxes. The price at the fábrica will be higher, but you won’t lose your smokes upon your return to the States.