User Activity

i have sold few things posted the day i got money into account left good feed back but people not leaving me any feedback and transaction was quick and hassell free what do i do
someone just won an item i had up for auction on the summary where it says itwm if paid invoice sent etc its flagged up item available for second chance offer what does this mean? They only just won item
i am new to selling do i put the start auction price at 99cents or do i put it at the price i am willing to accept for the item i also had a buy now price of $35 on the same item just not sure what to put in the start auction price box?