For all the reasons others have already stated, what you want is a Kill A Watt instead of a multimeter or another thing to buy. Plug this thing into the wall and then plug your appliances etc into the meter and leave it for a week. I will record total power draw over the duration so you can see exactly how much power is being used under normal operating conditions. With a little bit of math you can compare kilowatt hours consumed with your power company costs and figure out how much money it cost to use TV’s etc per hour.
This is so close to being right. You want your drain hose to have a high loop before it connects with the drain pipe. This site has more info and clear pictures.
https://homeinspectiongeeks.com/what-is-a-dishwasher-high-loop-and-why-do-you-need-one/