Marine grade vinyl from JoAnn's and Handcock's fabric stores.
With coupons and Apps. Spent less than a hundred bucks on fabric.
Spent 500$ at the upholstery shop and didn't have to do it. Got 6 yards red and 4 yards clay color.
Had the upholstery shop do it. I just bought the material and installed the seats after they were finished. Took me about 2hrs to install the seats and arm rests.