When the skunks started showing up on my porch, I added raised platforms (3 levels from about 2 feet tall to 6 feet tall) and fed the cats up higher. The possums can crawl up there, but I've yet to see a skunk up there.
The platforms sort of stair step higher and higher. I added a soft bed to one of the levels and my Lucky boy likes to sleep there now.
Oh but the skunks were sooo cute! There were little babies and everything! Ok, I know that's not a good thing....lol But I seriously want a skunk someday! I hear they are just like cats!!!