I rescued a lady with a quickie method I "developed," "invented," "thought up" myself. Her car wouldn't crank, but would kerchunk the solenoid. I told her I could try something, no guarantees, no liability, she agreed.
I took a Phillips head screwdriver and stuck the point in between the battery post and the connector and whacked it with a small wrench. Repeated around that gap, repeated on the other terminal.
"Try it now."
Started right up, effusive gratitude, money offered, refused, told her to get the battery checked and to have the posts cleaned, and have a nice day.
That good deed lasted about five days on my "good deed a day" ledger.
Better than any money, eh?
Terry, 230RN