I have a little supplementary WPF program that a lot of my clients use, and some of them are asking for it to be white labeled to appear as if it is one of their own products instead of mine.

Right now I just have one Visual Studio solution with two separate projects inside of it and I copy/paste code between the two. Its not elegant, but it works. Now a third company (and maybe even a fourth in the future) wants to white label my program.

99% of the code is shared between the projects, with labels, images, and some colors being the only differentiating factors. I build and publish them to separate "Click Once" installers/updaters, and separate download URLs.

Is there a better way to be doing this? I feel like I'm missing something obvious :(