As for the search in question: instead of "best commuter bikes for under $500", do yourself a favor and buy a beater bike for $100-200. The comfort is the same if not higher, but you stop thinking about your bike at all, and if someone steals it you buy another one next day without shedding a tear. My favorite ones are by fahrradmanufaktur, very solid, a new one will cost you a few thousand bucks, but after 5-7 years it still feels fantastic and you can buy it for a fraction of the price.