Halo Fountain #15 from Streets of New Capenna is a foil mythic card that currently sells for about $9.66 ungraded, with graded copies ranging from $10.50 at grade 9 to $12.00 at grade 9.5. A grade 9.5 copy sells for around $12.00 vs $9.66 raw. That's a modest premium, so grading only pays off for near-perfect copies.