The Vespin and the Aquia install somewhat differently than a normal toilet (and from each other) in that they both have an adapter that gets mounted on the floor and the toilet flange, then you mount the toilet onto the adapter. Neither is hard, and they both come with templates. The biggest difference is that if the floor is tiled, you have to drill holes in it, and that is something a plumber may not have the proper tools to do. If he does, it takes less than probably 30-minutes more to install than a normal toilet when you've done it before, but probably longer doing it the first time. If he's willing to read, it's not a big deal for someone with the skills to be a plumber. That doesn't always happen, as a lot of people are unwilling to actually read instructions!