I have almost always found rental cars a better option any way especially with more than one person sharing the cost. I always found it best to book through an aggregator online rather than walk up to a rental desk. Walking up to the rental desk always seemed to result in a refusal to let a car go out one way or a huge one way fee. I also found going airport to airport seemed to go smoother. The problem I see is that the whole rental car business has kind of gone to hell since covid and as far I I know is not yet back to normal. Prices are way high and cars scarce. They tend to promise and then not have them when you show up even though you prepaid. Avoiding high air travel times may help with the car availability. Absolutely don't count on getting a car on a big travel weekend.

Maybe buses can fill some of the gaps. I know greyhound sucks, but it might be better than cancelling the trip if they serve the area you need.