What is the trade value of Brock Holt, a utility player who turns 30 years old in June after posting an fWAR of a negative 0.9 in 164 plate appearances last year?
Bear with me, but Holt matches up with Seattle utility player Taylor Motter, who turns 29 years old in September after posting an fWAR of a negative 0.6 in 280 plate appearances last year.
Steamer600, which assumes 600 plate appearances for each hitter, projects 2018 WAR of 0.9 for Holt and 0.8 for Motter. ZiPS projects 2018 WAR of 0.6 in 385 plate appearances for Holt and 1.2 in 461 plate appearances for Motter.
Motter lacks Holt's All Star pedigree but the most significant difference in trade value is that Holt is owed $2 million in the second of his three arbitration years while Motter is owed the league minimum in the second of his six years of team control. Motter and Holt each have one option remaining.
If one WAR is worth about $8 million, Holt might represent value at $2 million, but my point is that most teams have players who can provide similar production at the league minimum salary.
Motter is not guaranteed a slot on Seattle's Opening Day roster:
https://www.rosterresource.com/mlb-seattle-mariners/