Sellers put NFTs on the auction market with a starting price (min price) and can set the buy now price for a period of time they set out
Set the step bid to have bidders place the bidding price at x% higher than the current highest bid
Bidders win based on 1 of 2 conditions, whichever comes first: bid price reaches the buy now price if there is a set or is the highest bid at the end of the auction time
The seller can follow the auction in real-time and cannot cancel the sell order before the auction ends.
See instructions here: https://s.tankbattle.co/auction-tutorial