Saks Fifth Avenue, which already switched to an appointment-only model at its Union Square store and laid off some employees, may not be sticking around much longer in SF, real estate experts surmise.The parent company of Saks, the Hudson Bay Company (HBC), just completed a deal late last year mergi ng Saks Fifth Avenue with two other luxury retail brands, Neiman Marcus and Bergdorf Goodman. And while Fortune reports this deal is likely, in the eyes of Neiman's and Bergdorf's customers, to negatively impact the integrity of those brands, it's also going to have ripple effects on the larger company's real estate holdings. As the Chronicle reports, the prominent Neiman Marcus store at 150 Stockton Street quietly changed hands as part of the merger in December, becoming part of the Saks Global Enterprises LLC portfolio. And with the Saks store diagonally across Union Square already seeming on life support, given the appointment-only thing, retail real estate experts say it may not be long for this world, especially with the company's lease expiring at 384 Post Street in 2027.When reached for comment, Saks Global told the Chronicle, "We continue to serve our San Francisco customers at our Saks Fifth Avenue and Neiman Marcus stores, and have nothing more to share at this time."With Bloomingdale's slated to close later this month, the departure of Saks would leave Neiman Marcus as the last remaining luxury department store in Union Square. And with Macy's slated to close after the company succeeds in selling its massive property on the square, Neiman Marcus would be the only department store in the area, full stop.It's a stark and fairly sad picture for SF retail overall. Just three years ago, the Union Square area had five of these large-scale stores, if you count Bloomingdale's and Nordstrom in the SF Centre (formerly Westfield) mall, and soon it could be down to one, with none offering the kinds of sales and occasional bargains of a Macy's. Stores like these are known as anchor tenants in malls, and serve the same purpose in a shopping area like Union Square, but the ways Americans shop may just have fundamentally changed — and the department store model seems to be struggling.No deal has yet occurred for the acquisition of the SF Centre property, which entered receivership two years ago after the departure of the Westfield Corporation, which surrendered the mall to its lender. An auction for the property, originally scheduled for November, has been postponed several times, and is currently set to take place on March 27, as the Chronicle reported last month. ...read more read less