The frenzied real estate market of the past two years is supposed to mellow out this year. Gains in home prices are expected to slow to single digit increases after two years of double-digit growth. Home prices in New Jersey rose 12% in 2020 and another 15% in 2021, according to the Otteau Group. They’re expected to increase another 5% in 2022 before declining in the next 12 to 18 months. And the declines — 10% to 15% — should last about three to five years, Jeffrey Otteau, a real estate economist and president of the Otteau Group said. But the cooling off hasn’t really affected prices yet, …