2003~2008 No Lights, No Crank, No Start...Help

Hi, I searched the forum and did not find a solution for this issue. My son has a 2005 V6 with the following symptom which began just a few days ago. No work or service has been performed on the car recently:

When the door is opened to enter the car, there are no interior lights or any other indication the car is alive with power. Turning the key in the ignition produces zero response: No dash lights, no bells, no cranking, no clicking from relays or the starter solenoid. The car behaves like there is no battery connected or the battery is completely dead.

However, attempting to start the car numerous times usually results in the car starting eventually, and when it does the battery is strong, turning the engine over rapidly. The local parts store tested the battery and alternator and they tested good. However I have received positive results from these tests before and later found out I had a bad battery, so they don't detect all bad battery conditions.

Where do we start looking? The only thing I am aware that might produce these symptoms is a bad battery ground. What else could be involved?

Perhaps related, my son tells me he has replaced the battery in this car 3 times, and he has only owned it for 4 years. My first thought was over-charging, but it seems like the parts store test would have seen that.

Thanks for any guidance.