In GSA negotiations, the base price defines what price the escalation is applied to and the actual or effective price may be above or below that base price depending on how the escalation factors move. A floor price is a level below which the price will not be allowed to go regardless of whether escalation would normally have taken it below that floor level. So normally, in GSA negotiations, sellers want a ‘floor price’ while buyers want a ‘ceiling price’ i.e. one that cannot be exceeded