You can do an easy job, or a really involved super clean job. This is the same for any car. The basic difficulty will change depending on what type of car it is, but then you can go on to put as much time as you want hiding wires, making stuff impossible to get to, etc. This is really the trick to a good alarm install; any thief can get into the car but how hard you want to make it to bypass the alarm after that is up to you.
So the question isn't "how hard is this to install", it's "how much time do I want to spend to protect my car"..