By Erin Boisson Aries, Global Luxury Real Estate Advisor, Douglas Elliman-Knight FrankThe best-curated property portfolios almost always feature a collector-worthy Manhattan residence or two. But owning real estate isn’t the only way to enjoy a foothold in New York. In fact, some ultra-high-net-worth individuals (UHNWIs) are now finding it easier to stay in a private residential hotel, where every detail and moment is expertly attended to. This new category of hotel – one that blends...