This is the most expensive type of generator, and models range from 5,000 to 20,000 watts. Standby generators are also the most convenient, since they are permanently mounted, and they kick on automatically when the power goes out. They run on propane or natural gas and cost $3,000 to $6,000, not including installation. Installing them is definitely not something you can do yourself; they should be installed by an experienced electrician.
