Sedo: receiving offer > push to auction

Got an small offer on Sedo but I intend to push to auction since I read that that way it'll be a free auction, but I need to know what will happen:

Example case: I get a $200 offer for a domain priced at BIN $1200 (FYI not real amounts)

1) Start bid: does the bid have to start at $200, or do I get to set it lower/higher?
2) BIN: can it be changed before and/or during auction?
3) Does auction start automatically with 1 bid from the original person making the offer or not?
4) Any way to add…

Sedo: receiving offer > push to auction