Originally Posted by
pitflyer
I'm doing the same thing, adjusting to cities that don't require a rental car. For example, I went to Fort Myers right before things really got nuts on rental car rates, I don't think I'd go there again now as that city is pretty spread out. But other places I've been to or plan to go to (Nashville, Las Vegas, Chicago, Ft Lauderdale, Miami, Orlando) all are fine without one. I do have tentative trips to Denver and St Louis and those are cities I'm not sure I'll be able to do much without a rental car.. it's too bad that makes those trips tentative for that reason only!
Where Denver is concerned, I think you'd be fine unless you have specific plans outside the city that are not well served by public transportation. A few of our favorite hikes are inconvenient (require an Uber/Lyft) via train, and we still don't bother to rent a car - even with normal prices. The lightrail is reasonably priced and very convenient, the 16th St Mall free shuttle covers downtown proper very well, and the city/regional public transportation isn't half bad.
If you find Miami/Ft Lauderdale to be convenient without a rental car, I feel pretty confident you'll be fine in Denver.