It give u an option to end the bidding for a certain amount instead of waiting all them days sorry couldn't reply earlier tablet died and no charger just went today to buy new one
to use gin you have to push the options on your auction site, and add an amount not less then 2000, it also cost credits to post get it now option, once someone places a bid you can not change anything about your auction, you can only add on to it hope this helps