Depends on the dealer. For instance, the one I used to work at would sell at cost (even for the plan deals) if you ordered whereas buying one off the lot it may be harder to get that kind of deal. Sometimes, the cars on the lots are from other dealers, so the dealer housing it doesn't get the kickback from Ford, only the original lot holder does. If this is the case, they are less willing to sell at invoice because some may rely solely on the Ford kickback for profit.