I like old bikes. Can't say why- character?? Its all about obsession- hate to put it that way but so it goes. 20 years ago I was really into balloon tire bikes and still have a Schwinn Black Phantom that I would love to sell. I doubt very much I will get even half of what I have into it.
And that is a great example: the cost of the bike is the cost of the ticket to adventure. If you are concerned about how much you are going to sell if for then this *may* not be the right sport for you. In some cases you can do well flipping bikes, but it seems that there must be an easier way to enjoy a hobby.
Right now I am having a lot of fun with British 3-speeds. Seven or eight years ago I was fascinated with hand-built vintage French bikes (which I never seem able to afford). After goofing of with a variety of bikes I decided to pony up for a frame custom-built to be what I wanted- for the kind of riding that I seem to do the most. I like the idea of owning a bike for a long time so this still seems like it was a good idea. But that is not to say it quenched my curiosity about what is around the next bend. I used to really be into older Campagnolo- after owning a few higher-end machines so equipped, I find the 3-speeds to be more interesting...
Bottom line: if this is a hobby for you and if can follow your dreams don't worry about what is the most sought-after. That may not be the bike you really want. IMO what is important is what is the bike that makes you want to go out and ride. Racers don't do that for me- they tend to handle too quickly and often have a harsh ride- a torture rack after an hour or two. I have a Schwinn Paramount from the early 70s (which is a 'sought after' machine without question); it is set up with touring geometry and is much easier to ride. So my advice- try a few bikes and see what it is that keeps you coming back. There is a lot of variety out there so just enjoy the ride and seek advice so you don't waste too much along the way... in that regard, be resigned that it will probably happen sooner or later
