Walking down Lake Street this weekend, I passed a marquee at Hallmark Realty that read:LUXURIOUS 4 BD YARROW POINT GATED LAKE VIEW RENTAL. $17,500 PER MONTH WITH GOURMET CHEFS KITCHEN.What exactly does $17,500 a month get you? Hallmark’s Web site doesn’t post a picture of the 5,080-square-foot, one-story property, but when I called Hallmark, real-estate agent Bonnie Lindberg said that the property, which is a fully furnished private estate that the owners have put up for the summer, is “quite nice”: water views, bamboo floors, granite and slate finishes, high-tech wiring, wine cellar, nanny’s quarters, said kitchen (with a big bar and lots of preparation areas), and a three-car garage. Does the gourmet chef’s kitchen come with a gourmet chef? For that price, no.