That's a whole lot of money.
How much more is max?
I guess he can receive $27,250,000 a year so, 109 million for 4 years.
Max is (projected, based on next year’s salary cap):
Celtics can offer: 5 years, $169.7 million (this is the $170 million Simmons and Murray have received).
Other teams could offer: 4 years, $125.8 million
Over four years, Celtics could offer: 4 years, $131 million.
In other words, Brown could get an offer sheet next summer that beats this offer from the C’s by more than 50%. So no way he agrees without a much higher number.
My proposed offer (that I’m 95% sure is legal) is: 5 years, $122.9 million. That’s a max contract next year, with the maximum allowed decrease every year. As far as I can tell, to get the 5-years in an extension, Brown needs only be offered the max salary in year 1.