Originally Posted by Andy_K

Probably the biggest question apart from bike fit...do you enjoy working on bikes? You said time is your most coveted asset, but just like money time is only valuable when it is spent. If you are interested in spending time restoring a bike, that can be very rewarding. If you just want to have and ride a beautiful classic bike, that's still possible but it changes the options a lot. For example, you asked about a vintage frame with modern parts. It's relatively unlikely that you'd find what you're looking for ready made. You could buy the frame and parts and pay someone to assemble it for you, but that gets really expensive in a hurry. Gathering all the tools you need to do it yourself can be expensive too, but the joy of good tools is a topic in and of itself. If you don't want to spend time and money on the build/restoration process, that leaves obviously you with looking for complete bikes in good working order. It sounds like you're willing to put some time into restoration, but it isn't clear how much or which parts you're comfortable doing yourself.

Regarding selection of the candidate bike, tubing is probably a better indicator than brand. Not that you'll necessarily notice a big difference between different tube sets, but it's an indication of the market the bike was targeting and therefore has a correlation to quality. You can't go wrong sticking with Columbus SL and Reynolds 531, and those are plentiful. Once you're into the 1980's, there were also some good Japanese tube sets under brands like Tange. The brand of the bike will probably give you some satisfaction, and it's also a rough guide to the kind of geometry you're going to get.

The brands with big reputations come with correspondingly big price tags that don't necessarily get you anything extra other than the name. Bianchi, Colnago, and DeRosa, for example, are all great bikes in high demand, but (with the exception of low end Bianchis) it's hard to find them at reasonable prices. A slightly off brand can be a real bargain and often has its own appeal once you learn more about it. For example, I have a Colnago C97 and a Machiagi-built Coppi Reparto Corse, both from the late 90's, both with very good original paint, both with chrome lugs. The Colnago has Columbus Thron tubing while the Coppi has much lighter Columbus Genius tubing. The Colnago cost me three times as much as the Coppi, and by most objective standards the Coppi is a better frame.

Mainstream American brands like Trek, Specialized, and Centurion were producing very good quality bikes in the early 80's, but in my opinion they aren't as sexy. They're really good for figuring out if you're going to enjoy riding a vintage bike though. I see that you're in Wisconsin, so you probably can't walk out your front door without tripping over a vintage Trek. Don't shy away from them. The 600 and 700 series bikes especially were very nice.

Consider tire clearance. As you get into the mid-to-late 80's you start losing the ability to use tires wider than 700x25. You're probably aware that this trend has reversed and many people are recommending 28's or wider these days. This is a personal choice, but it's something to consider.