The door itself was easy enough to install. We are not DIY people and learned a lot about our door. It's an exterior door, metal and glass. THAT was a chore and an adventure to cut! Cutting the door and getting it back on the hinges was the chore. Installing the cat door was easy. Our door is just under 2 inches thick. The frame of the cat door does not cover the 2 inch width, but even those of us who are non-handy/DIY should be able to realizing that going in. We wound up taping the inside where the door was cut. Not a professional job, but it can't be seen. The door is a great price, the door itself was easy to install and it works. No complaints.