Happy to have a winning bid to post.
Did extensive research on prices and Discount Hawaii Car rental and Costco were giving me about $500 for the trip. Best prices were on mid sized SUVs, of all things. Started w/$13/day and denied, so went to $15/day. No go. Changed to compact (which is all we need) and stayed at $15 and won for a total of $331, with Hertz. In that Hotwire reportedly was $304 for compact, I may have slightly overpaid (didn't want to end up w/Thrifty if went Hotwire). In that I have 3 weeks, likely should have used some of that time and tried even lower for a compact, but don't know that it would be worth the additional time. This is $162 less than my back up reservation via Costco. Thanks for all your hard work!