I have a dump truck with 4 foot high steele sides on it. I have seen a couple other trucks in my area with roll up tarp systems. I want the convenience of covering my loads with a tarp that rolls out and back in. I am not looking for anything really expensive like the electric ones I have seen. I just want the hand crank kind. Do any of you have one of these? Where did you get it? How much? Thank You.