Pick a brand of battery powered lawn equipment that you want to use (string trimmers, blowers, ect), and get a chainsaw that matches. I know that the power will be out when its time to use it, but keep 3 batteries charged and you won't need to worry about that. 3 batteries is enough to do quite a bit of work so long as you not cutting everything into firewood lengths. Cut it short enough to move it, and that's it.
Sitting there on a shelf, the rubber (intake boots, fuel line, oil line) on a gas powered tool will eventually dry out just like the old brake and vacuum lines on a car that sits in a garage or barn for years. If you use it from time to time, then you can run into carb issues if you use fuel with ethanol in it. Even with non-ethanol fuel, you still have varnish that can build up. Bottom line is that if you use it, it WILL eventually have starting issues. If you don't use it, eventually the rubber will dry out. With battery tools, when you squeeze the trigger, it turns on. Besides, battery powered string trimmers are nice and light