PU vs EPS: what changes about the repair
Two constructions, two resin systems
Most boards are built one of two ways: PU (polyurethane foam under polyester resin) or EPS (expanded polystyrene foam, almost always under epoxy resin). The repair has to match the original resin system, not just patch the hole.
Polyester resin will dissolve or eat into EPS foam on contact. A repair done with the wrong resin can do more damage to an EPS board than the original ding did. Epoxy resin is compatible with both foam types, which is part of why epoxy repairs are common even on PU boards.
Why this matters before you call a shop
Not every shop works on both constructions -- some specialize in one. Knowing (or being able to describe) your board's construction before you call saves a wasted trip, and it's exactly the kind of detail this directory tracks per business rather than assuming.
If you're not sure which you have: EPS boards are generally lighter for their size and the foam looks like white foam beads under a ding; PU boards are denser and the foam is a uniform, closed cell. When in doubt, a shop can usually tell from a photo.