Setback Measurement on Play Fridge & Sink?

I'm working on the original play fridge plans as my first project. There is clearly a setback for the toekick, but the distance isn't specified. The sink also has one, but I don't see a measurement listed there either. Judging from the photos of the kitchens that have been made so far, some did a setback and some made theirs flush. Does the measurement matter? Is there a standard setback measurement for most projects? Can someone suggest a measurement so I can get started? =D