He declined to be identified by his full name because his business license only authorizes him to make clothing, but he essentially resells imported garments.
The new rules will mostly affect clothing stands and boutiques, but could also hurt the supply of things such as artificial nails to beauty salons, or fabric, buttons and zippers to dressmakers.
It could also make it harder for some Cubans to visit family abroad. Trips are often funded by agreeing to bring back large bags on behalf of someone who pays the airfare.
The Cellphone Clinic's Matos said he began doubling his normal purchases this summer and has stockpiled enough parts like fragile electronic ribbons to stay in business for two more years, no matter what.
"If buying pieces becomes more expensive, if people are bringing in less, you have to reevaluate and prices will have to rise," he said. "It's a bad thing, because if you raise the price not everyone will come like before. It's not worth it, you know?"
It's not clear that any state-run operation would offer some of the Clinic's services, such as unblocking an iPhone 4.
Separate tax rates cover food and electronics, including 400 pesos (or $17) for a Cuban to import a 32-inch or larger flat-screen TV on a first trip, and $400 on subsequent travels.
Authorities insist they're just trying to improve service at Cuban airports, where excess baggage clogs conveyor belts in passenger terminals. In mid-August, state-run website Cubadebate published Customs officials' explanation of the tariffs along with several examples.
But it did little to ease concerns, judging by the dozens of exasperated reader complaints posted in the comments section.
"Why should a Cuban citizen have to pay the taxes in a currency in which they themselves are not paid?" said a poster identified as Roberto Suarez. "That's not fair. I don't travel, but I don't see the logic in that."
Some said the regulations could force entrepreneurs to turn to black-market goods pilfered from state-run concerns.
Others, however, predicted that Cubans, famous for their knack for finding a make-do solution to any problem, will figure a way to sidestep the duties.
"Something will be found to get around this," said Maria, another clothing vendor who also would not give her last name because her business activities exceed the scope of her license. "It always happens in this country. It's like they say: 'He who creates the law, also creates the cheat.'"
Associated Press writer Anne-Marie Garcia in Havana contributed to this report.
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