I think the conversation is going/will go like this:
Bill: We want you back, but at this price. (Salary the size of Jacoby Brissett in Indy)
Brady: No, I'm done taking discounts.
Bill: OK, then you're welcome to look around.
I think there may be teams that can convince themselves that adding Brady at his asking price would be worth it as they have teams currently being held back by their QB play. Tampa and Indy are the first teams that come to mind. Good, offensive minded coaches. Some good pieces around the QB. Poor, or limited, QB play.
The Raiders and Chargers have been brought up as places that could use Brady as a ticket selling draw in addition to his qualities as QB. Whether it'd be as good a fit footballwise remains to be seen.
Now, I'm not saying that any of these possibilities would be advisable or good, it's just that Brady wants to keep playing and Belichick may not want Brady to play for him at a premium cost.
The possibility also exists that Kraft would side with Brady and Belichick would go. That also seems inadvisable, but we're in uncharted territory to be sure.