Build a Box (Local Toronto)

Looking for a carpenter to help with a simple project to create a shaping box I can use to train my dog.

Dimensions 12′ wide, 35′ long, 4′ high

Notes:
There should be a non slip padding on both sides (inside) and on the bottom)

There should be a slot on the front where another slice of wood would sit (front gate should be removable)

There should be a little grip handle to easily carry

Would should be stained