Here's my chance to see if you really read these things. My transaction with Ziffit was selling used books back to them. I had a good experience withn ZIffit in the areas of customer service, price, delivery, etc. They paid more for my books than anyone else offered, and their payment was fast...super-fast. But, this is what happened....when lifting the box of books I was to send them, I injured my back, and have since had to spend A LOT of money on doctors and had A LOT of sleepless nights. My injury may take 6 weeks to heal...not worth the $9.52 payment from Ziffit. Moral of the story....get a big strong man to lift, or use two small boxes instead of one large. Books are heavier than you think.