BIll, you might want to mention that kids & dogs multiply the dirt factor by ten!
We got a patio mat and you'd be surprised how much that helps.
Also, the walk around twice is good advise. I walk around once I have everything hooked up and again just before departure checking the lights, etc.. And you're right, you'll be surprised how many times you'll find a little something.
Oh yeah. Look up! that darn tv antenna is up there.