their production numbers solely to pre sold units. They announce a model, offer collectors the option to order in advance, if they so choose. They produce a finite number of each model, and each unit is numbered. That number is not based upon the amount of units that they have pre sold. One recent example is their recently in stock Fiat 130 Berlina. It was available for pre order for months, and now it is in stock, and available to anyone who wants one. Perhaps there are companies that only produce the quantity of units that they have already taken orders for, I tend to doubt it.