where I live, most people selling torches didn't buy them (grandpa did) so they don't know how much new ones cost. The asking prices are astronomical and the torches are very heavy and outdated.

The victor J100, 100FC, and 100C are pretty common, not horribly heavy, and there are definitely framebuilders using them. Not a bad choice if you can get a good deal on a setup. I have thought about getting one so I can do light welding, but I wouldn't want to use them for framebuilding, too tiring.

I ended up spending about $500 on tanks, torch, regulators, and hoses. I got a Smith AW1A, which seems like the most popular torch for framebuilding. The Victor (also made by Esab) J28 is also popular. One way to save money is to substitute propane for acetylene. The welding supply store should be able to sell you adapters for standard grill-style propane tanks. You'll have to check with the suppliers about propane compatibility for regulators. Most people report that they can use an acetylene tips for propane. The torch makers sell propane tips, but they usually just add a small divot at the tip to help keep the flame from detaching and going out.

Here is an older thread where we covered the subject in a little more detail