from my experience, make sure the specimen has zero skin abrasions. drip acclimation is a must. i constantly hear “do not expose it to air when transferring” but mine will occasionally hang out at the water line and “feel” the surface like other starfish are wont to do (i think it’s skimming the surface for organics?)
a well-established mature, stable tank will go a long way. i believe they eat primarily bacterial film and microfauna off the rocks, but i’ve read of people spot-feeding them pieces of krill or shrimp occasionally.
i don’t know them to knock over corals the way a turbo snail or a cowrie might do. mine tends to hide a lot (and i hardly have any fish in my tank at the moment). make sure you don’t have fish that will potentially harass it (like toby puffers).
also be aware that linckia can host parasitic snails so watch the LFS specimen closely before purchase and during acclimation.
good luck with it if you take the plunge! :)