Every other room gets planned around how you live. This one gets a car count.
Garage
+1
Three walls, one ceiling, and the door that undoes all of it.
Insulation
Bedroom outlets. Code makes sure one is nearby. It does not make sure you can reach it.
Electrical
Blocking. Why a 2x10 for a towel bar is not overkill.
Framing
Most of you do not have a fix for this. Here are four.
Plumbing
The number it costs now, the number it costs later, and the exact words to ask your builder.