I did not think I needed to invest in oxyacetylene all though I would.
It's the only way to go. Besides brazing, you will also be able to weld steel and quickly heat up metal parts to bend or harden them.
Many uses outside of gunwork too. I've used mine to weld patch panels in old cars, straightened frames with a rosebud tip, welded up lawnmowers and trailers, etc. It's an invaluable tool.
I'll also agree with these responses.
I just use the small size tanks (B?) so they're not so cumbersome. About 2 ft high and 6" dia.
It cost IIRC $13 to refill the acet not long ago and it lasts a long time for this type work using small tips like #0 and #2. It's fast heat,, means you're not standing there for 5 minutes wishing the part would come up to brazing or welding heat wasting gas. If anything you have to learn not to over heat stuff.
I bought my own tanks, that way I just take them in and refill.
The torch kits (hoses, gauges, torch, some tips and accs) are sold quite inexpensively for about $100 and up.
I'm sure pro-welders have an opinion of brands but for what I do,,,,mine happens to be a Harris
The 'repairmans' type kits which includes the tanks (but they are the smallest ('MC' size) and a carry pack to carry everything around in can be bought for around $250-$300.
The small tanks might not be what you need if you're going to get into large welding projects in auto & fabrication type projects, ect.
I bought a small cart that fits the next up size tanks I use and it makes all the difference in the world using the unit. Plus the safety of having them secured well and not just leaning up against a wall or bench.
Just some of the options around.