clamp-on DC ammeter myself, because it's also good for measuring things like starter current, etc. They're not particularly cheap, but they can certainly be had for less than my Fluke cost me.
This one, for example, is $90. http://www.electrical-contractor.net/The_Store/EX/MA200_220.htm The 400A range is nice for automotive work, because starters (usually) draw less than this. -- Jim
