I like to buy junk tinplate repair, it repaint, it and then keep it for while then sell it. Since I never buy pristine collector items very often I find along with the missing paint, dents and rust that the solder joints holding the piece together have cracked with age. Just today I took the roof off an old 114 and the side almost fell off due to cracked solder joints. In the past I used a heavy duty Craftsman soldering gun and it didn't work very well. For Christmas my wife bought me a Harbor Freight hand held torch ( $14.99) and what a difference. This thing makes quick work of any joint repairs. A little flux, a couple of metal binder clips to hold things together and my car is back together better than new.
That's $5 less than my 20year old Craftsman version, looks identical.
I've used mine for everything from soldering to lighting fireworks.
I even tack brazed with it a few times.(small)