What is the outcome of the bid in Chapter 3 of Chains by Laurie Halse Anderson?

The outcome of Chapter Three's private slave auction is that both Isabel and Ruth are sold to Mr. and Mrs. Lockton.  

Mr. Robert is attempting to get rid of Isabel and Ruth as quickly as possible.  He didn't pay for them, so any price that he can get for them is a profit.  Mr. Robert has a possible buyer for Ruth and Isabel in Mr. and Mrs. Lockton.  He offers the two girls as a two for the price of one buying option.  Mrs. Lockton isn't that terribly interested, but she knows a good deal when she sees one.  Right before the deal is concluded, Jenny blurts out that she would like to buy both Ruth and Isabel instead.  Madam Lockton may not desperately want the two slaves, but Madam Lockton hates losing.  Jenny's offer is seen as competition, and Madam Lockton doubles her offer on the spot.  Jenny can't top the offer, so Isabel and Ruth are sold to the Locktons.