I am not yet at the point where I need to consider the issue of hiding the models. I have a Mondeo Sallon with a large boot, but with the lid sloping down so multi masted ships might be a problem.
I have thunked about the issue in quiet moments and wondered about sewing covers to put over the top of the model shrouding the masts and yards but shaped so that they are not pressed by the fabric.
Perhaps a corset like frame sewn into the cloth to hold it to shape. This would also prevent the collection of that horrible sticky old dusty grime that ruins old models rendering them (for me anyway) the cause of days of sneezing, snorting and nose blowing. What about carrying them upside down in frames?