As you might expect from the description of the deal, pre-owned devices are those that haven't been renovated to bring them up to a certain standard, and might also be missing some of the accessories that you might expect in a refurbished product, which typically includes all the accessories that a new device ships with. The original price of the iPad 3 (WiFi, 16GB) was $499.99.
Cowboom says the following about pre-owned devices. At the very least, a pre-owned product is tested for power and functionality. Refurbished items, though, have been refurbished by the device manufacturer (AKA Apple).
Pre-owned describes products that have been purchased, opened, and operated. Then, for a multitude of reasons, from buyer’s remorse to functionality, the product is returned to the store. When a pre-owned product is processed by Cowboom, it is tested for power and basic functionality. When buying an item that is not brand new, ask yourself these questions:
1. Factory refurbished or Refurbished items frequently come in store-like packaging. This is usually noted in the item’s description.
2. How much visible wear are you comfortable with? Pre-owned items and certain grades of refurbished items may have visible imperfections. If you are planning on putting the item in a protective case, this may not be as important to you. Or if you are particularly hard on your items, the cosmetic condition may not be as important as having a device that works. Usually, the more scratches on an item, the better the deal you can get
Cowboom includes a grading scale for its refurbished items. It is:
A-B-C grading scale
If a refurbished item has been graded on the typical scale, one can safely assume it’s in full working condition. The A-B-C scale simply refers to its appearance:
A: Appearance is close to new
B: Appearance may show very slight signs of wear
C: Scratched or bearing some other cosmetic imperfection
Those opting for pre-owned, rather than refurbished iPad 3s can opt to select the "best available" iPad 3.
This is the iPad 3, not the current generation of the iPad, or the iPad 4 (or fourth generation, as Apple prefers to call it). Apple has scheduled an Oct. 22 press event that is most likely to cover the iPad 5; based on history it will ship to retail on Nov. 1 (as will a new iPad mini).
This explains, naturally, the proliferation of iPad 4 and iPad 3 deals.
It is unclear how large a supply Cowboom has, but we'd run, not walk, if we were you.