I have a patio in my condo that's about 4' below ground level (the building was build on the side of a hill). I just got permission to paint the wall, so I am going to do a mural. I haven't decided if I will use spray paint or brushes, I'm thinking a combination of both. My problem is that I can't decide on the subject to paint. I'm thinking either a large salt water aquarium scene or the Chicago skyline. I need more ideas, so let's hear 'em. The wall is about 7' x 4'.