You can do a search for Featherweight on this board and the Internet. There is a wealth of information available.
It is good if you know what to consider when you find one. I was so excited to find one at an estate sale I just said "I'll take it" without even taking it out of the case. Luckily turned out to be in wonderful condition and a Centennial model. After learning more about them would surely have looked it over thoroughly.
They are out there in great condition and poor condition and this may determine the price.