You leave your "maximum" bid price that you're willing to pay. The system will place your bid at the lowest price within that range. If someone else bids and your "max" is still higher, the system will increase your bid to the next higher bid price in fixed increments. If the next bidder outbids...
Just a solo sentinel where you can stick the other "flying" statues on. Well everything is still in the design phase so anything can happen. Considering it's gonna be done by the same guy who did the Magneto, I'm sure it'll be awesome nonetheless.