This is a good price if you’re in the market for an automatic backup generator. Sale runs through today. These are made by Generac and include the transfer switch (normally $6-700 more). 17 and 20kw options available. Installation is more complicated than hooking up an interlock kit like many do with a portable generator. Would need an electrician and plumber/mechanical person for the gas line, unless you’re comfortable with both. Generally requires a permit to install. These also take a lot of gas to run, so it may require an upgraded gas meter (for natural gas).
https://www.costco.com/Honeywell-17-Kw-Automatic-Standby-Generator.product.100313165.html
https://www.costco.com/Honeywell-20kw-Standby-Generator-W/-Transfer-Switch-Model7063.product.100321543.html