It's a lot easier to make ships / vehicles if you take a picture off of google images and try to replicate it! Try picking a super basic, small boat to make and then progress up to mega-yachts. Trust me, I've wasted a lot of time trying to make mega-yachts without the experience to lol. Also, snow is a great medium. It obviously doesn't have stairs but you can make slabs of ANY size with the snow decoration block.