“Location, location, location”—that enduring house-hunting tip doesn’t apply just to the residential market. Exactly where to open (or relocate) a new store is perhaps the most crucial decision a retailer can make. Unless you live in a tiny town, procuring the perfect space will require the know-how of a good commercial real estate agent—one who not only will show you what storefronts are on the market, but who also can negotiate a favorable deal when it comes time to sign the lease. Reputable realtors have deep relationships with landlords, says Jay Luchs, a Los Angeles–based commercial real estate agent who’s placed numerous retailers on Rodeo Drive, among other luxury shopping rows. “I also know a lot of the sites that aren’t obvious,” he says, “because I’ve been doing this for 12 to 14 years. My ­specialty is showing [retailers] what’s not on the mark