I'm traveling from SD to YNP this fall and am curious about lodging. Will be leaving Mt Rushmore enroute to the YNP East Gate, but was wondering if lodging should be in Cody or Jackson? My plan is 4 nights in the YNP/GTNP area before heading south towards next destination - Estes Park, CO. My concern is breaking up the initial travel day (SD to YNP) and keeping costs low. Oh... and did I mention I would be traveling with a 2 year old? Alone?
Any assistance is appreciated.

It is a pretty long drive from Mt. Rushmore area to YNP. With your situation especially I would definitely stop in Cody vs. Jackson. It would probably be cheaper also.

Any reason you don't want to stay in the park?

Staying in the Park isn't something I'm opposed to, but I have been unable to find hotel lodging that fits in my planned budget ($80-$100 night). If you know differently, I'd love to hear about it.

Its really to long of a drive from Cody or Jackson for visiting Yellowstone for four days. A lot of driving to and from the Park... Jackson is ok for the Tetons but you may want to investigate a place to stay in Gardiner, West Yellowstone or Cooke City for the Yellowstone part of your trip.

Agree with Red Rock. My suggestion for Cody was to break up the trip from SD. Maybe 2 nights in one of the other places he suggested and one in Jackson area on your way out.