We really liked Denver last year. We went in August though. If you go a little off the beaten path, I think you can get places on Airbnb fairly cheap. I found cheaper places once I started searching away from the main tourist area (like Estes Park, etc)
We had decided we wanted to rough it and found a tiny cabin in the woods with no electricity/running water for US$60/night. It included unlimited firewood and unlimited drinking water and every possible amenity (for a rustic cabin lol!). It was my dream vacation spot.
https://www.airbnb.ca/rooms/9114774?s=N-dcgs1a I loved that
- I had my fill of the outdoors
- had trails right onsite
- was secluded and yet not truly remote (civilization and all modern stuff was close by)
- it was only 1hr 20 mins from Denver airport (my DH doesn't like driving too far)
- had the huge Indian Peaks Wilderness literally FIVE MINUTES away with amazing hiking
- had other trails within a reasonable driving range
It was a CHEAP vacay because we cooked at the cabin and mostly just hiked/enjoyed the fire. Also skipped Rocky Mountain National Park itself to avoid the extra 1hr drive and the $20 admission fee.
Another spot we enjoyed was the Smokies (we spent a week a couple of years back). I think u can fly into Chattanooga or somewhere in North Carolina? Not sure since we drove. I don't think this is as accessible to an airport. We stayed on the NC side of the Smokies deep in the mountains (way less tourists).
I loved that
- cabins were dirt cheap. We had a 5 bedroom gorgeous cabin perched on the side of the mountain with no neighbors in shouting distance overlooking a lake...for a measly $90/night. It was crazy and the cabin was BEAUTIFUL. Spacious with all the amenities, leather reclining couches, etc.
- activities were cheap on this side of the Smokies. White water rafting for $30/pp, horseback riding for $30/pp, AMAZING tubing for $3/pp (to rent - free to bring your own), and of course, the Appalachian Trail and the FREE Smoky Mountain National Park was right there.
The one drawback for me is that I don't find the Smokies as beautiful as many other parts of the US and Canada. The value is tremendous though - we only spent $1k for the 4 of us, including gas, food, activities, rentals, a few restaurants....and would have spent much much more doing similar things somewhere else. My kids have asked to go back to go rafting and tubing. I posted on FB about all our adventures all week and a friend ended up booking the same cabin! I sent her a full breakdown of everything we did and she ended up doing most of the same things :) The Pigeon Forge side is pretty cheap too, but everything is a notch cheaper on the NC side which adds up.
Good luck! Another option is to visit Canada. With the 30% drop in the Canadian dollar, it really is a good value for your US dollar. Plus, Canadian national parks are all free in 2017.