We have propane at our home and had a propane generator installed last year.
If you have natural gas access, go this way.
Ours is hands off and easy. Every Monday at 1PM, it starts up and runs for 5 minutes. The company that installed it gets notifications (thru the innerweb) if there is a malfunction (none yet).
I would use propane over gasoline just for the convenience (don't have to buy gasoline and fill the generator).
I have no idea about solar, but I'm of the general opinion that anything solar is not technologically up to speed.