I am building a 15 foot sailboat with a retractable centerboard. I am close to painting the hull and then turning the hull to begin building the cabin, deck etc. But when I turn it is a perfect time to have a trailer to set it on. I really don't know what type of trailer to look for. I do want to find a used one to save money. I was wondering if anyone had any suggestions on what to look for and what to avoid?