Apparently newer cars require the jumper be removed after 3 seconds while the ignition is still in position 2. As far as buying the tool, if you are uncomfortable following a well documented procedure, or want to add something new to your toolbox, then fine. You can also make a simple foolproof tool with a current limiting resistor and diode to prevent accidental misconnection. I have no problem spending money to keep up the maintenance on my car, so it is not a matter of skimping or being cheap.