Vehicle rental rates have skyrocketed but that's because demand has gone up and the supply went way down. Apparently companies shipped some of the cars to the mainland because demand was SO low this past year and rates consequently tanked. I wouldn't call it gouging, it's basic supply and demand. OTOH, it is something to think about. Some people even ship their cars when they are considering longer stays: https://www.flyertalk.com/forum/hawa...ernatives.html

I will repeat that I think it's best for first-timers to hit the sites on O`ahu first and then go to the Neighbor Islands rather than the reverse. I think they will appreciate both more in that order. The transportation issue is a whole other reason to do O`ahu -- the public transportation system isn't exactly fast but it's there and it's extensive. I have literally taken TheBus around the island a couple of times and in many ways, you can get a better appreciation for it that way. Having said that, OP is talking about 2022 so there's a whole year for rates to change and rental car availability to settle out.