Manufacturing generators required skilled labor, materials, and overhead, all of which can drive up the price. If you need to have a generator professionally installed, this can add to the cost as well. If your home needs a backup generator, the installation may be complex. First, the generator probably needs a foundation. Next, you will likely need gas lines and electrical wiring. This may require the help of a certified electrician. Lately, you will need to test the generator to ensure it works properly. All of these steps are in addition to the cost of the actual generator. Generators need to be built to last, thus requiring high quality materials and advanced technology.