Thanks, both of you. The boat on the trailor with the mast laid down is about 28'. The beam is about 7'6" but I'll have to check the exact spec. So the container is still at least a possibility. Then there is the question of the cars. And, come to think of it, perhaps the RoRo would be good for the boat too, since it's already on the trailor.
I'd be glad to get any other comments or ideas.