I don't know what the markers would be, but assuming they're like pied markers there's no guarantee that the animal is het for anything, so buy from a trusted breeder.
Not true. Het Reds are visual morphs and they do have much more reliable markers than pieds.
~*Rich
1.0 100% Het Albino
1.3 Normal
1.0 Spider
0.1 Mojave
1.0 Pastel 100% Het Goldfinger
0.1 Pastel 66% Het Goldfinger
0.1 Pastel PH Goldfinger