For a DIY own property, you can get away with a lot less equipment. For someone that does it for a living, I go for professioanl grade overkill. I too use the Stihl, but a 450. I have all the blades, even a scratcher like a circular saw blade. A bicycle handle, and a comfort double shoulder harness. Customer really want to see that when you are billing hourly.

My saw is an ancient Shindiawa 680. But close to bulletproof. I also augemented my income by cutting firewood and cooking wood for selling. Ran all the way up to a 30" bar. Far too dangerous, way too impractile. No matter how much penile envy I received, it was not worth it. I'm all the way down to a 18" bar. Big saw, little bar. Cuts extremely fast. Never throws a chain with so little sag. That 30" came flying off one time and just missed my forearm. Never used it again.

Which brings us to Todd's very good point on safety, how I forgot to mention that is inexcusable. This equipment is unforgiving. You rarely get a second chance or a harmless oops. At the end of a long day once I got distracted at the very end splitting oak on a 50 ton splitter. My hand was between the wood and the backstop and I was so very lucky the piece was small and split with my hand there. I would be Capt Hook today if not. I always wear industrial gloves, a hard hat, full visor, the screen kind because I can't work with fogged up shield. And full coverage mouse ears. Steel toe full length work boots also. Can't tell you how many times debris has hit my facemask, or safety goggles. Branches fell on otes, or whipped into them brushcutting. Don't just ignore the pages of safety instructions in the front of the operator manual. Live by them. Never work tired, distracted or inattentive. Never.