well, that's consistent with my original concern. That maybe I could have installed it that way if I'd never first installed skrooge without the PPA. But I'm not sure.

I have this dependency error when I try to install skrooge-kf5:

skrooge-kf5 : Depends: qtbase-abi-5-5-1 which is a virtual package, provided by:
- libqt5core5a, but 5.7.0+dfsg-1+16.04+build5 is installed.

I suspect either the dependencies could be adjusted or I could be assisted in manually adjusting some of the libraries I currently have installed. I'm really hoping to not have to reinstall my whole system!

I need guidance on how to fix my setup so that skrooge-kf5 will successfully install.

I checked what depends on various versions and most of the whole KDE ecosystem as I have it now depends on libqt5core5a > 5.7.

Perhaps if you just update the skrooge-kf5 binary to accept that newer version of the library (even if it doesn't require it), then I'll be able to install it.

Well, nobody posted here to notify me, but today plain old skrooge package was updated to 2.5 in the neon repo itself! All good, that's the situation I'd expected all along. Cheers!