Not more expensive, just also expensive. A F. X. Tourte bow will be the most expensive you can find, a couple of hundred thousand euros. Than there is the 20-100k € range, the french bow region. Beneeth you get some less know french bows, good baroque bows and some of the best German and English ones.
If you go to the region <5000€ you get the usual master bows, both modern and baroque, living and dead. If you leave the thousands and move to the hundreds you get some remarkable old Markies without name, some decend baroque ones and a lot of manufactured junk.