Car Audio Design Project

Hi everyone, I am a design student currently doing a project for Kicker Audio. I’m working on researching the installation process of car audio systems. I’d like to get some input from enthusiasts on their own experiences. Here’s a few initial questions: Would you do the install yourself, or pay to have it done? How much time did your install take, if you did it yourself? Would you say that certain cars are easier to install systems in to? Does the difficulty of the install change depending on components that make up an audio system? Would you need any tools beforehand to do an install, and if so, how many? If you could change anything about the install process, now or in the future, what would it be? It would be a great deal of help to hear from anybody that can provide some info! Thanks!