MacBook – What chargers are compatible with A1226

Actually you should be careful when using a charger that doesn't come with your laptop. Apple's official word on the matter is:

Make sure the proper wattage adapter for your portable computer is used. Select the appropriate power adapter for your Apple portable computer. You can use a higher wattage power adapter, but you cannot use one with less wattage without potential operating issues. (here + discussion here).

In the good old days (Powerbooks) we used to get all sorts of odd logic board hassles when using the wrong charger. These days it does mean a slower charging time but it can also mean the (very) rare logic board damage or hardware funkiness.

I wouldn't purchase this machine unless it's still covered by AppleCare.

Inspect it closely for nicks and dents, indicating a drop. I would check the Console logs for any indication of ongoing OS level problems.

Unfortunately testing hardware can take a while, but is worthwhile before buying. Run AHT (see http://support.apple.com/kb/HT1509?viewlocale=en_US&locale=en_US) and do the quick test. To do it you'll probably need the original disks that came with the machine.

The only other thing I can think of would be to verify that modules such as bluetooth, WiFi, Ethernet etc, are showing up properly (and information is being populated in) system profiler. To get there, hold option while going to the apple menu - it's the first option.

Listen for loud fans, can indicate overheating or bad sensors.

Aside from that... it's always risky. Check Apple's stock of refurb units. They come to you refurbished by Apple, with a 1-year warranty, and often don't cost that much more than a CL unit, but with much less risk.