Must mirror the other techs. Been in this business for over 36 years. My father was in it for 38 total, and we overlapped each other 20 years . MUST Have insurance before you do Job #1. You don't tighten a gas line properly, fire starts and KABOOM there goes everything you own. Or you don't tighten a water line properly and ruin a 15,000 dollar wood floor. Don't even think about working without insurance. I carry a 1,500,000 liability policy and it isn't that badly priced. Shop around.
I do all non warranty work, and have built what I consider a powerful, and sizeable loyal customer network. I prefer NON WARRANTY WORK> I get a large amount of my work from referrals. It is, in my opinion, the BEST way of getting customers. I don't want to deal with the paperwork, and all of the stipulations involved with warranty work. However, when starting out, If you need to fill a certain amount of hours, doing warranty work and making a smaller amount of money than your non warranty work is better than no money at all. In the beginning, it can fill out your hours until you build enough of a network of customers to keep you busy week after week. Remember also, the more diverse you are the less chance you have of sitting in your office with nothing to do. For example, I repair all domestic appliances, Coin operated and commercial laundry equipment (my specialty, up to 400 lb commercial washers and dryers. I am a service entity for 3 companies, and the manufacturer gives my name out regulary to customers needing service. Great thing, warrantys are very short for commercial equipment and all work is non warranty), Dry Cleaning equipment, Presses and steam equipment, and Commercial Kitchen equipment. My commercial clients include 4 Laundromats, 4 Dry Cleaners, 10 Restuarants, 2 Catering Operations, 8 Hotels and 3 Health clubs to mention a few. These type of clients constantly have work for me. Mix in the Home service calls, and I have at mimimum 60 hours a week of work. Last week I worked over 80 hours. I had a DJ business in the past but no longer have any time for that. My message - DIVERSIFY. Don't put all your eggs in one basket. I also can do HVAC, but gave that up. Remember, you Cannot Do Everything. When my domestic work slows, I always have work at laundromats and hotels.
Over the years, I have tried every form of advertising. Besides the phone book, I also have a presence on the web, and use several key newspaper ads in small town papers to enhance my advertising. EXPERIMENT . Keep what works, eliminate what doesnt. Join some business help groups, they will help you with marketing, setting up business, Legal issues, etc.
One other piece of advice. Do Good work. Make the customer happy no matter what. Better to loose a little money than have a ticked off customer. One bad referral is worse that 10 good ones. Bad news travels. And don't work on items you cannot fix. Always appear to be knowledgable even if you are working on a new appliancem you've never seen before. People call you because you are an expert. Act like it.