Hi Paul6ppca,
Here in Phoenix, I have been collecting old lights starting earlier this year. I have mostly 2D and 2C lights dating from the 1930s to the 1970s -- after that I would think they are largely contemporary -- and I have never paid more than $20. I never found them priced above $20. This includes "octagon" bezel lights from Eveready, Bond, and Rayovac [Copper] using screw base bulbs; 2D, 3D, and 2C Sportsman and Captain models; other assorted chrome consumer 2D lights by Eveready and Rayovac.; metal magnet lights; and angleheads, etc.
In some parts of Northern Arizona, I have seen them sold at higher prices, but not significantly over this amount. There seems to be almost an attitude of "how do I get rid of these? -- maybe someone will take them off my hands". I find that once they are cleaned up, batteries and bulb replaced, they work 95 percent of the time.
I've obtained most of the lights for significantly less than $20, including a 3D Captain for $3 at a thrift store and a 3D Sportsman for $6 at an antique store. Recently, I purchased a "Solid Copper" 2D octagon head Rayovac for $10 at an antique store.
Note that there are many old non-metal flashlights that are interesting as well. Enjoy the hobby. Flashlight Museum has some price guidelines -- more importantly they have useful information and provide a guide for estimating the age of your flashlight.