Receptacles are usually set at "hammer handle" height to the bottom of the box.
This can be anywhere from 12-16 inches up, depending on your particular hammer. Be sure to use similar hammers on the same job, or else you can get inconsistent results.
I prefer them to be higher than lower, since as you age (and everybody does), it may become a problem bending over to reach those outlets as your back stiffens up.
I usually place switch and counter-top outlets at 44" to the bottom, making them all consistent. Others prefer to place switches higher, but that is an individual choice.
Finally, things like thermostats are usually placed higher, and we install them at 54" to the bottom.
But if you have short folks involved, you can put `em at a lower height ...