FVV option must be picked up to trade him. At 44m, I don't think the Suns will find anyone willing to trade for Fred during the season, so they would be stuck with him for 1 year. Booker, Beal and Fred is not a championship team, so the other assets they get back would need to be considerable.
However, compare that to Rudy's contract, or Vassell, both have significantly more future money guaranteed. Neither is going to be a trade asset that returns more picks. FVV is at least a one and done option for them.
The other thing about this trade is that you may need to give KD a 2 year $122m extension as part of the trade. If that's the case, that would be problematic for the team's cap situation, unless hes willing to take a moderate discount. Maybe he agrees to 2 years 90m? I know it's not 73 win Golden State, so he may not be willing to drop 30% in value, but he's 36, and the extension is for his 37/38 years. That's a huge liability given his injury history.
If that extension is part of the trade, do you still do it?