My power company is absolute garbage. I have multi-hour power outages at least once a month, along with several "bumps" that take us down for short periods. Probably once a week. (I come home to reset clocks and such). I need a backup solution to run my house when this occurs.
Priority goes to maintaining climate in the house. I need to keep the house below 80 and above 65 or so. I am on AC and propane furnace. Well pump and pressure pump need to run, or I get no water, and I have a stand up deep freezer. 1620sq ft house, 3 bed, 2 bath, unfinished basement.

Need an automatic transfer switch for when I'm not home.
Looking at Generac, Briggs, Kohler, whatever. Any particular one to get? I'm thinking 12k+ watts. I have propane on site, but would actually prefer gas/diesel (but I know those get spendy).