Starting your own business can be challenging, but it can be done and very rewarding. I do warranty work, it seemed to help me, to get started. I am in a rural area od Oklahoma. I am getting lots of C.O.D. work from customers who at first were warranty calls. Biggest thing is keep your over head low, low, low at first. The only advertisement I have done is a refrigerator magnets with my company name and number and I have a small sticker I place inside the refrigerator, near the model number tag. The rest of my business has came from word of mouth. I worked for Sears for 12 years, then bought a MR. Appliance franchise, (Costly mistake) and sold out is 2008, then I moved to where I was raised in Oklahoma, and went to work for A&E for 1 year and quit and started my own business. I started working on the side and decided if I could make as much as I would make in a weak with A&E at 20.00 hour, then I would start my own business within weeks I achieved that goal and left A&E/Sears. Sears had changed a lot since I first worked for them. If they would let you just be a great technician, that would be fine, but all of the upselling and long hours is for the birds. As far as parts inventory goes, I have built up a good inventory over the parts 5 years and I will take the parts with that I think I might need. I carry some parts in my truck bed tool boxes on my S-10 pickup, but I can't carry it all, so I load up what I think I may need before I leave for the day. I built a 40x40 shop to keep my parts and truck in. I do not have a store front. One big thing is to charge enough money.
Most appliance businesses that I know of, that have failed , have failed because they charged too little and had too much overhead. I wish you well.