Apple sent out invites yesterday for a pre-Halloween Mac announcement. The MacBook Pro is believed most likely to get updated at the event, but honestly iMac is likely not out of the question or maybe even MacBook Air. So to avoid buyer’s remorse, maybe wait until after October 30th to buy a new machine.
No new Airs are expected but you never know. You could always find somewhere with a generous return policy in case you need to take it back if new models are announced