I think 5 years maximum. He will 32 already to start next season. I would offer him $125M guaranteed: 25, 30, 30, 35 for 2018-21 with a 35M option for 2022 ($5M buyout). Whether he takes it may be more about how he sees the Jays' chances to compete in the near term along with how he feels about playing in TOR, versus going to the highest bidder.
As much as Vlad prefers to play 3B, he will be much happier in LF for the Jays than 3B for the Bisons, so we could see him in LF in 2019 with Donaldson at 3B. Then again, depending on how Smoak does next season, there could be an opening for an everyday 1Bman in 2019 (or sooner if Smoak were to - God forbid - revert to historical performance).