Alright, that sounds good to me, I can bid that much but in order for you to actually receive 1000 credits someone else needs to bid at least that much too (that's just how auctions work)
Sorry for the late reply, my internet is being sketchy... The easier thing to do would be to edit your auction, change the starting bid to a higher amount, and update the shipping cost. To do this you need to go to the auction page, press "Edit", and make these changes :)