A rental sitting at the harbor all week earns nothing — return it before you board.
HDOT’s visitor page lists buses, bike share, car share, the trolley, rideshare and taxis, and gives no cruise parking. That’s the harbor agency’s own page, not a forum post, and we found no cruise lot at either pier.
Aloha Tower Marketplace’s garage, run by SP+, says overnight parking is not allowed there, so it doesn’t work for a cruise. Don’t plan on it.
Harbor Court at 55 Merchant Street is open 24 hours, with a $21 weekday maximum and $3 evenings and weekends, cash only, per a parking-listing site; we found no published multi-day rate. A daytime maximum doesn’t tell you what a week costs, and we won’t guess one.
Keep a $41-a-day HNL car through a 7-night cruise and the rental alone is about $419 on our numbers — before any parking, which we couldn’t price. Hand it back and rent again afterward.
Bringing your own car to the ship is a different question, and our Hawaii parking page tracks what we can confirm on it.