I've heard that a lot of services in anything vaguely construction have gotten banana's. But ya this seemed extreme.I’ve made a number of large purchases over the past 4 years and one thing I’d strongly suggest is to get at least 2 if not three quotes on any large purchase. $16K for installation is beyond ludicrous. In June 2020 I had a 22KW Generac installed along with the 400A (utility required it) ATS. I believe out the door that cost me around $8000. Not sure if the larger portables have an oil filter but those that don’t will need the oil changed more frequently I’d suspect.