Title said it all. Will fly into HNL, then to OGG for a week, then to Lanai and back to HNL. Thinking about ferry between OGG & Lanai, then fly back to HNL directly from Lanai. Will be staying in Westin Maui in OGG. Where can I return my rental car if I were to take the ferry in Lahaina (without heading back to OGG airport?)

And I am pretty prone to seasickness. But I think I can handle 1 hour ferry. Is it pretty rocky or normal? (I have no problem going to Nantaucket Island or from HKG to Macau).

Thanks.