My commuter beater bike was $500 off craigslist that was lightly ridden for <500 miles judging by the original tires. It is Fuji 4.0 LE cyclocross thing (more upright riding than a pure road bike).
New it would have been probably $800 new (co-worker has the next size up identical bike and paid $800 on "sale") and checked the boxes for having disc brakes and not being junk. I've put another ~$400 into it for tires, tubes, fenders, rack, shop repairs (wheel true and bottom bracket after 6k miles), chains, cassette, 2 chain rings (never buy FSA crap), etc.
So my advice is to find a comfortable bike with mid-range components and don't look back. ~$1k is a good price point these days.
Getting top-end components only makes sense if you are racing, and makes the regular maintenance expensive and painful. In fact, you should look up the cost of the main drive train components before you buy. Expect that every ~1-2k miles to replace the chain, every 2-4k miles to replace the cassette and main chain ring, and maybe every 4-6k miles to replace the derailleur. If you weather is not wet and crappy all winter you might do better than me. Some of the new 1x11 or 1x12 drive trains are painfully expensive to replace wear items on, like ~$100 for a low end 12 speed cassette vs more like $30-40 for the old 9 or 10 speed ones. Factor that into your choice before you pull the trigger.
I have a second bike for "fun". It was $1k for a fully rigid mountain bike (Kona Unit-X) for bikepacking, but that is a whole different category of hobby/fun rather than commuting utility. It probably has another ~$400 of add-ons to get it the way I wanted it with cargo cages, an added front derailleur/crankset (1x11 drive trains are not my favorite...), frame bags, butterfly handlebars, handlebar tape, etc, etc.