1
general::
Phrase(s): bargain for something [and] bargain on something
to plan for something; to expect something. • We knew the project would be difficult, but we didn’t bargain for this kind of trouble. • I bargained on an easier time of it than this.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
1. Also, bargain over. Negotiate about something, usually a price. For example, In open-air markets it is standard practice to bargain for the best price. [Late 1300s] 2. Also, bargain on. Expect, be prepared for, as in In planning the picnic, we hadn't bargained for bad weather, or I hadn't bargained on John's coming along. [c. 1800] For a synonym, see COUNT ON.
American Heritage Idioms