Edwin of the Iron Shoes by Marcia Muller

It's Sharon McCone's first case as staff investigator for All Souls Legal Cooperative. She knows nothing about antiques, yet she has an affection for Salem Street with its charming mix of antique and curio shops. Now elderly dealer Joan Albritton has been found dead, stabbed with an antique dagger.

Her neighbors are shocked. Recurring vandalism has them frightened. Ferreting out the facts will take Sharon from the chaotic jumble of the junk dealer's establishment to a museum where San Francisco's most elegant socialites gather. But it is not until she is alone in Joan's dark shop with Clothilde, the headless dressmaker's dummy; Bruno, the stuffed German shepherd; and Edwin, the little boy mannequin in the ornate iron shoes that she will have the chance to discover the murderous secret someone will kill -- and kill again -- to keep.