Bigger boxes tend to be harder to maintain and keep. The cost to acquire them was also high, making it affordable only to the wealthy. The tune is also important because if you had popular tunes, people would be more willing to buy it than to acquire one that plays an obscure tune especially in the case of non-interchangeable music boxes. The materials used to make good music boxes were rare and expensive, such as rose wood, which made them rather resilient to aging if well-taken care of. Another good place to check is online specialty stores that sell collectible music boxes. If you do some research you might find a Reuge music box worth collecting. Make sure they are old, in good condition (for its age) and is limited in quantities. It's a pretty good bet that if you have one from the early 1900s that the music box is hard to find. If you are not an expert at fixing these music boxes, make sure you have an idea what restoring a piece might cost. Otherwise, it's a lot better to go ahead and pay the premium for a working music box than to take the risk of paying exorbitant restoration costs for a collectible music box. The price will also tell you a lot of things.