Vintage and antique collectables vary from collections of vintage dinner plates to antique French furniture. They vary in scale as much as they do in cost, and some will take up your time and effort to find whereas others will be readily available.
Antique mirrors are beautiful, first and foremost. You can find all sorts of styles in local vintage stores and in online antique boutiques, from classic French gilt to simple driftwood. Choose mirrors that reflect your personality, and make sure that they are an appropriate size for the room.