inexpensive cover
I store my 170 on a trailer with the mast down. I bought a relatively inexpensive (under $40) generic boat cover from Wal-Mart and modified it slightly at the stern end slightly using scissors, some nylon cord to reinforce the new edge, and Goop adhesive. Anyplace you cut, leave about 1-2 inches extra, fold it back on itself, and glue it down with the Goop. Spring clothespins every few inches help hold the new seams in place until the adhesive sets. You can reinforce the edge seams with nylon cord, and if you are careful with the adhesive, you can form a long narrow pocket along the edge so that the cord slides freely through it. Let cord extend beyond the fabric, and tie loops in the ends of the cord as an attachment point for tie-downs, bungee cords or whatever.You may be able to cut and trim an off-the-shelf generic cover to fit around your mast and shrouds.I would have preferred a white cover, but all Wal-Mart offered was a light silver-grey, and I haven't had any problem yet with heat build-up or hull cracking. Numerous posts caution against dark-colored covers, and I agree.If you have deeper pockets than mine, there are custom-made covers available on-line for the 170, or you could have one made by a marine upholsterer.