As time marches on, American pony and muscle cars are becoming more scarce and valuable. The expensive part is great, so long as you already have one (or many). If, however you're on the hunt for one, that's quite another matter. The price that you're likely to pay for anything that's restorable is likely to be quite dear. You might even be tempted to tap into your kids' college funds, justifying the purchase by thinking that you can share the old car hobby with them. Thankfully, there are still some less sought-after muscle machines out there that are just waiting for some smart folks to snatch 'em up. Consider if you will these three fine A-Body Mopar models from Plymouth and Dodge: the 1970-76 Plymouth Duster, the 1971-72 Dodge Demon, and the 1973-76 Dodge Dart Sport.