$75 is good rate.

I have a weekly at Maui and that is $190 for a economy, or $220 for a midsize. So your $75 is not a bad rate at all.

I would not go PCLN or hotwire route because of the insurance credit card provided. There is a high probability you may incur damages in Hawaii rental - break-in is not uncommon, for example. You would not get the benefit of credit card rental insurance should you go PCLN route.