The feat was, to my knowledge, first published in Deities in Demigods, as a 3.0 source. The feat very clearly has a metamagic cost of +0.A spell cast with Eschew Materials can be cast with no material components. Spells without material components are not affected. Spells with material components with a cost of more than 1 gp are not affected. An eschewed spell uses up a spell slot of the spell’s normal level
It should be noted that, for whatever reason, your game going into Epic level, taking Eschew Material becomes a bit of a power play, as it is a requirement for possibly one of the second most exploitable feats in the entire game, Ignore Material Components losing out only to Epic Spellcasting as a means of generating wealth (casting time of Fabricate and the high level requirement really thwarts it).