Absolutely my idea, and I sold him on it. I had been looking at them for about 5 years before we got married. Then we looked at commercials, didn't like what we saw, knew we could make it better. It took me about a year to convince him he wanted to build one.
I had a real advantage as my husband is a welder, machinest, and likes to work with wood, and I am the finisher.
He didn't really want to take on a big project, he is so busy with his own business, but I kept showing him ideas, and once I found this website, and Steve's "handbook" and bought that for him, so he had a general idea of how they go together, he was ready to go. Once he drew a profile, I knew I had him. And although a lot of work, building it together was really fun. He designed the profile and basics, we decided on all the details together, he engineered it, built the frame, and did the heavy lifting. I did all the wood finishing and the motivating to get it done, or it probably still wouldn't be (he is not a completer, I am)
He would not allow me to use a hammer after seeing the damage I can do when I miss, and I am now not allowed to use the powersaw after cutting off 1/2 my thumb (yes, really, but not until the trailer was finished, it was a very last project).
And we both love it, and we have threatened each other we can never divorce because we would have to cut the tear down the middle.