Ken Kahan makes a living building homes. A specialty? Luxury apartment complexes in Los Angeles neighborhoods such as Palms and Silver Lake filled with mostly market rate units, but with a handful of income-restricted affordable ones as well.It can be a good business, but lately less so.“We have pulled back,” said Kahan, the president of California Landmark Group. “The metrics don’t work.”Across California and the nation, developers moved to start fewer homes in 2023, a decline some experts say...