I decided to add singing pumpkins and a skeleton face to my display this year using foam board. The link to the video is below. I've already painted these and put the lights in so it's probably too late to waterproof them. I used acrylic paints but didn't paint the backs. I'm going to make some snowmen out of foam board for my Christmas display and am wondering how the paint holds up on foam board over time and does the paint fade over time? I will paint both sides of the snowmen if necessary and am wondering what the most cost effective (cheap) waterproofing product there is.