Road trip to Colorado & Wyoming from Missouri- Hotel question
 

I will be traveling with my parents to Colorado and Wyoming from Missouri the end of July. We will be visiting Estes Park, CO, Douglas, WY (family reasons), Jackson Hole, WY and MAYBE Yellowstone. Just curious if we would have to make hotel reservations ahead of time or would it be possible to travel around and stop whenever we feel like it which is what we would prefer? I don't want to run into a situation where everything is booked. We are not too picky about where we stay as long as it is clean. Any thoughts?

Yellowstone is only an hour from Jackson, and your park pass covers both parks; shame to miss it!
And yes, for peak season in the Estes, Jackson, and Yellowstone areas you should probably (definitely) have reservations.
However, they are usually easily cancellable (sometimes the day of the stay), depending on how you make them, and if someone has a laptop or a tablet (or e-reader with wifi), you can make new ones/cancel, as you go.
p.s. If someone in the group is 62, the lifetime National Parks Pass for $10 is the bargain of the century!
http://seniorliving.about.com/od/tra...n_age_pass.htm

I think if you want to stay in Yellowstone, you had better have reservations ahead of time or you might wind up staying outside the park and wasting a lot of time driving back and forth.

Estes Park/RMNP has not been as busy in summer the past several years as it used to be. However it would still be good to have reservations in advance. I would not want to be out on the road searching through all the hotels trying to find one that has a vacancy at the last minute.

Thank you so much!

All that has been said is true, but there really are people who book the parks a year in advance and then cancel last minute. I scored a cabin at Lake lodge in Yellowstone in June one year. Along the route you should have no trouble near the interstates, pick up the discount coupon books at the welcome centers and look for areas with lots of motel/hotels even if it is a day you can't use the coupon.