- Roll on roll off sounds the best, why aren't all boats shipped this way?
This is often ideal for smaller boats on trailers, but in some cases larger boats on cradles. As it is under deck, your boat is far better protected from bad weather at sea, but.... it can be more expensive. - Reducing your length or height can make a big difference.
Costing on RORO vessels are normally calculated per cubic meter. So if you can take off a swim platform thats say 2 feet, then multiply by the height and width, you will be amazed at the difference in your freight bill.