I was age 14, still 3 years shy of N.J. legal minimum when I bought a Ford Anglia 105E for $35.00. It was pretty clean, but had water in the steering box and would only steer willingly to one side. My father rope towed it home for me with a very burly friend of ours steering, and me passenger. I had great plans for it, but a $14.00 used steering box and an opportunity for a $100.00 MG TD made me sell it, for $
100.00. It took me several decades to make another profitable sale! Photo taken by Dad of me and TD on arrival, again by rope tow.....Traded the TD still as a project for a parts car Sunbeam Imp many years later!
In reply to TurnerX19 :
My first car I bought cost me $300 at age 14 was a 1953 MGTD, running, driving. (Briefly, 43 miles)
Sitting down in my shop now? 1953 MGTD. No the engine isn’t original.
Got my first car, a '62 Mercury Comet, for free from my grandfather who had been using it as his daily driver.
Traded it off for a '71 Torino GT after a year of driving it in high school.
In 2002 I bought a 91 Mustang GT from my dad for $4800. He had bought it in 95 for $12000.
In 2017 I sold/traded it to my brother for about the same amount of money I paid to facilitate selling my first house. It sucks some, but he actually drives it and takes better care of it than I did.
1949 Jeep- free. Belonged to a local business. It had a flat tire, they tried to use a fork lift to lift it and ran a fork thru the gas tank. Put it in a shed and forgot about it. I talked them into letting me haul it away. Put in new gas tank and after burning valves a few times in the flathead four I ordered an adapter from JC Whitney and put a Chevy V-8 in it. Awesome acceleration! Sold it to a cousin after a few years for $400. Interestingly
Honda Civic CVCC purchased for $250; sold wrecked to a junk yard for $50 a year later.
First car was a 1981 Porsche 924 that my dad towed out of a field for free. After many years of racing it went to the junkyard. Maybe a $50 profit? 
A pair of Renaud 4cv's for $25
Drove one to high school for a year
1978 Ford Pinto. Bought for $250. Pushed it home, fixed it by driving a pencil into the side of the carburetor to plug a vacuum leak. Drove it two years and sold it for $400. It still had a pencil driven into the carb. Not the same pencil though, the first one got blow out by a backfire.
I wish I would have kept that car.
79 Mustang with the 2.8 V6.. bought for 1700 in 87, sold for 200? In 88 after the lower pulley broke and tore out the front seal. I loved the car but hated that motor
