Twin Star Cars was founded in 2000 to make parts for models I wanted. Initially all were HO. After a number of years modeling HO I made the move to Proto48 and found that many things I wanted were not available or were not as high a level of detail as I wanted. SO the quest continued and more models have been created. I have found that making things available to others helps to off set some of the cost as well as produce a higher level of detail in the process. I tend to make what I want. If it happens to be something you need then I am happy to provide it as long as the molds or supply lasts. Once the first run is gone, there is no guarantee I will produce it again but I try to weigh the cost of inventory with the probability that it will sell.  Other parts I consider stock that can be replenished and I will work to keep inventory available.