As I posted earlier. James Jones said they would have been interested in a 3 or 4-year max deal. He knows he is dealing from a position of strength.
It's not just the max contract, it's also the escalators. Other teams can only offer a four-year deal with 5% increases (The Suns can offer 8% increases if they want). I think JJ would be fine giving Ayton that deal. They also get to wait until the end of this year just in case Ayton declines, reverts, or even gets injured. Ayton can demand a trade but JJ can just say "no, you are too valuable, we are not doing it." The Lakers did that with Kobe. If he pouts and dogs it, they will trade him. JJ is big on committed character players, and they would not want a player that dogs it on their team.
He could sign a max deal with another team with a PO for year four. I think James would be fine with that too.
Looks to me like JJ plays chess, while the ESPN talking heads think he should be playing checkers.
So. I think that as soon as free agency opens, the Suns should lay a four-year deal starting at max level on the table. Make the escalator 6%. No one else can match. If he signs a lesser deal with a 4th year PO, just match it. Now if Deandre really steps up this year and approaches star status, just pay him.