I think you guys so far are hugely underestimating what Smart will get from somewhere.
Marcus is averaging 30 min per game and his per36 averages are 12.5 points, 4.6 rebounds, 5.5 assists. He's an elite defender and can play 3 positions. He was the #6 overall pick of his draft. He is thought of pretty highly around the league based on the ESPN Top 100 rankings. Let's look at the free agents this offseason who were most similar to Marcus.
Otto Porter Jr just got 4 years, $104.
Andre Roberson just got 3 years, $30.
James Johnson got 4 years, $60.
Olynyk got 4 years, $50.
Dion Waiters got 4 years, $52.
Tim Hardaway Jr got 4 years, $72.
Tony Snell got 4 years, $46.
KCP got 1 year, $18.
Patty Mills got 4 years, $50.
Jeff Teague and George Hill each got 3 years, $57.
Jrue Holiday got 5 years, $125.
Everybody's opinions vary, but I'd say out of Marcus + those 12 guys, that Marcus probably ranks somewhere around 4th-5th.
I'd expect him to get signed to a RFA offer sheet somewhere around 4 years, $70 mil (+/- $10 mil) if we do not reach an agreement with him.