Great cheap heavy duty tarp source: bill board advertising vinyl canvas material. I have twice found 60 X 40 foot used bill board material for $50. So what if the inner material had Honda Civic or Mystic Lake Casino printed on one side. I used for the frame assembly, 2” PVC pipe for frame work, Guerilla tape and stainless ratchet clamps to secure the uprights to stanchion poles, golf balls tied into a monkey fist to tie off the tarp to the boat hull. I got 4-5 seasons out of a tarp. Remember, the goal is to keep vast majority of freezing rain, ice and snow off the boat. Helps to have another person to muscle up the canvas. On my Catalina 30 I split the tarp in three sections. Good luck.
