âAdvertisement promoting the Imperial Academy. An Imperial Academy was a military training program run by the Galactic Empire, and primarily focused on training both the enlisted and officer corps of the Imperial Military.
People have created accounts and bid on their own stuff to try to raise the price. If caught, they are deleted from the system by E-bay. As many people wait until the last few minutes to make a bid, it is probably the surest way to win something.
All they can see is the current highest bid. If the current bid is $12, and you enter $20 as your maximum bid, you will be the new highest bidder at $12.50. If you are subsequently outbid, eBay continues to make new bids on your behalf until your $20 limit is reached.