We all know iPads are made by Apple, so
I hope you mean that you would be buying the iPad from Apple.
If you purchase refurbished or open-box directly from Apple, there will typically be a one year warranty on the item.
Warranty begins to diminish substantially as you distance from Apple, as BestBuy is only 90 days, and it only gets worse with other vendors.
Not only that, Apple will not service it at all if BestBuy or anyone else has physically opened up the iPad.
Apple's warranty is voided by any non-authorized party working on the device.
Beware pursuing that deal that is too good to be true... It usually is.
Only purchase electronics from authorized distributors.
Save yourself the grief.