iRobot Roomba 3000 Robotic Cleaner

I purchased this Roomba as a Christmas gift for my Mom. It was filthy when I opened it, and has never worked, despite weeks of very patient attempts. The battery was dead, and the seller admitted to having sold it without trying it out first. Because with the purchase of a new battery I would pay the equivalent to a brand new Roomba, (and have no guarantee that it would work, even then) I've had no choice but to return the item.
I have my own Roomba, which I purchased from an Ebay seller, and absolutely love it. I know they are typically a great product, and highly recommend them to busy housekeepers/moms. If I were to rate the Roomba product-line in general, I would give it an excellent score. However, this particular item, having never worked, deserves a rating of poor.
Thanks, LO