“I feel useful; I’m independent,” said Ms. Álvarez, who opened a small cafe in November at her home in this scruffy town 25 miles from the capital, Havana. “When you sit down at the end of the day and look at how much you have made, you feel satisfied.”

Eagerly, warily, Cubans are taking up the government’s offer to work for themselves, selling coffee in their front yards, renting out houses, making rattan furniture and hawking everything from bootleg DVDs to Silly Bandz and homemade wine.