I'm having a bit of a debate with myself right now. I wonder if it is a good idea to buy a newer car when I hardly drive my current car at all (I work out of my home 80% of the time these days, so I only drive about 5,000 miles a year)--it's not quite as extreme as buying a luxury car or a sports car just for trips to the supermarket, but it's as close as it gets to that extreme. At the same time, however, I am not sure if it is a good idea to spend good money to fix all of the problems I'm contending with in my current car (the same 2002 Pontiac Grand Prix I bought in 2008), only to be met with other problems down the road. The main problem right now is that the weatherstripping is apparently not able to keep out moisture, so I occasionally have windows frosting up on the inside (and the windows aren't rolling down, either--moisture must have gotten between the windows and the seals, causing them to stick together).
I'm always looking for new ways to save money. I know I already mentioned this on my Facebook timeline, but I have a portable jump-starter that I've had for 12 years (it's a Car Start 1000, similar to the one shown here). However, when jump-start a dead battery with it last month, it didn't work because it wasn't holding a charge. I figured it was time to start looking for a new portable jump-starter. But then I realized... before I buy a new one, I've got nothing to lose by taking the old one apart to see if it's got an internal battery that I can replace myself. And lo and behold, I found out that it did (see the picture below--that dark gray block that the booster cables are bolted to is a 12-volt sealed lead acid battery).
I managed to find a replacement battery (on eBay, your friend and mine). Last Wednesday, I successfully put in the new battery, giving my 12-year-old Car Start 1000 a few more years of useful life. I ended up spending $29 on that battery (by comparison, a brand new Car Start 1000 goes for $60 on Amazon.com). But I should let you know, replacing the battery in a portable jump-starter is not easy. In addition to the usual hazards associated with sealed lead acid batteries, putting the Car Start 1000 back together was not as easy as taking it apart was. In retrospect, maybe I should have looked into this project a few years ago... that kind of battery usually doesn't last much longer than a few years, let alone 12.