Sure, I do this all the time. In fact, I think my car budget is STILL ahead. My $350 Roadmaster was hit by a garbage truck and they wrote me a check for $2800. And I specialize in three-figure cars, so selling them for a profit is not challenging.
The only car I remember selling for less than I paid for it was my POS convertible Sebring. I lost $150 on that car. That's been my biggest loss in about 4 years. Grr.
I'll give you some chains of sales. Sold $650 240SX for $1200, bought $900 P71. Extra $300 bought my second Roadmaster, a blue '93, that I traded for the Chrysler Newport, which I sold for about $700. My $250 Caprice Classic went for $800 to a guy who had an engine for it, $500 of that went to that Sebring (grr!!). Hmm... How far to go back? :) A small portion of my MR2 proceeds bought a '91 Civic hatch, which became a ZC-swapped CRX, which became a 302 5spd F150, which became an '86 GTV6, which became an '86 745ti, all zero-dollar even trades.
I haven't added to my car slush fund in years. Yep. It's possible!
