This is the best suggestion so far, as other suggestions (like 'box') are neutral (emotionally), whereas 'clutter' lets the customer know that what you're doing is HELPING them remove things that are negative (emotionally speaking) in their house.

If you added in a positive effect to this (think along the lines of cash4gold), so clutter4cash or something (it has some rhyming to it too, which has been proven to improve recall of product names), then you're onto something. [EDIT: or is that 'cash4clutter'?? I never know which way around the before/after should be!] [EDIT 2: PPS - great idea for a service!]