With Dubai a major travel destination for businessmen, who often have to stay in hotels for extended periods, Alexander Chatzieleftheriou spotted an opportunity. His four-year-old startup leases apartments from owners at market value, furnishes the place and rents it out to companies for their employees at a 30% to 60% markup—which still comes out cheaper than a month-long hotel stay. The service is available in Athens, Istanbul and became available in Dubai last August.