As the economy recovers and hotels begin new construction — Smith Travel Research reported an 18.5 percent increase in hotel rooms under construction in April — hoteliers that took pains to differentiate brands are now, if not tossing those notions aside, at least testing their limits. These combination hotels, which share buildings, meeting rooms, recreation facilities, back-office operations and sometimes front desks, are sprouting in cities like Los Angeles, New York and Atlanta, and in smaller markets like Austin, Tex.; Huntsville, Ala.; and suburban Baltimore. The hotels typically pair an extended-stay property like a Marriott Residence Inn or Hilton Homewood Suites, with a limited-service hotel like Marriott Courtyard or a Hilton Garden Inn or Hampton Inn. White Lodging of Merrillville, Ind., a hotel developer, expects to open a combined Hyatt Place/Hyatt House in Denver in 2015. Choice Hotels has linked a Sleep Inn with a MainStay Suites in Port St. Lucie, Fla. “The trend is intensifying as the cost of building and running hotels is becoming more expensive and growing as developers seek creative ways of building out real estate,” says Henry Harteveldt, a travel industry analyst with Hudson Crossing, a consulting firm in San Francisco. Marriott estimates that 12 percent of Residence Inns being built will be joined with other Marriott brands. Hilton has 15 combined hotels open in the United States and Canada and 15 more under construction. Get the full story at The New York Times