In the army i was taught to do a voltage drop across the battery, each connection, and the starter. It diagnosed bad connections as well as bad battery and/or starter. We only had a voltmeter. Across the battery is different, but by putting the volt meter across a connection and closing the circuit, you will see over 1/10 volt if the connection is compromised, up to 12V if it is totaled. Same in checking the starter drop and starter to ground connection. You need to start with a higher setting on the volt meter and then check at lower settings so you don't fry your meter. I always liked my little inductive amp meter.
