I had my first brake buddy "installed" by CW 10 years ago since the installation involved a constant power supply in addition to the cigarette plug. It also involved the break away switch and a connection to the brake light circuit. After that's all done, installing the system each time is easy. When the BB died, I purchased a new system from them. The new one isn't a plug for plug replacement since they have made changes and "improvements". Installing the wiring and connections for the new one required several calls to their tech help to get it functioning, so I can understand the question of having a new system installed. I don't have an opinion of using it with a trailer.