That is sort of a tough question. What area do you live in, what is your competition
? Also what is the average income in your area, population density of your service area. If you live in a rural area, you might have allot windshield time vs a suburban/city area. Starting out is always a little rough, you need to build up a repetition and establish a good name for yourself. Internet advertising is the best way to go, google and facebook work okay for me. I would stay away from Home advisers, and places like yelp. There are home warranty companies that offer extended warranties, you will have to do your research on them. Some are slow payers and don't pay well. Warranty work is okay, it does not pay well. However you do get access to information and training that might otherwise not be available to you. I would join a couple of trade groups, like MSA World, USA (united servicers association) and also Appliantology.org. Those are good trade groups to join. I would only recommend this trade, if you have good people skills. You have a good electronics back ground and are willing to keep up on training, and keeping your skillset updated. It's not a bad way to make a living overall.