When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Another test that has not been mentioned: Disconnect one terminal of the batt and hook up an ammeter in series with the battery and the disconnected terminal and see if there is a drain. There might be a nominal small drain due to radio memory or alarm, but it should not be much.