> This is potentially less important if you negotiate over the price of a sofa on Craigslist.

Perhaps off topic, but speaking of sofas and CraigsList no one should buy a new sofa without checking a few weeks on CraigsList's free section. At least in New York City, every day sees plenty of new ones for free that will otherwise go to landfills even if like new.

My two sofas came free from people in my building, both like new.