Reset: what is retained depends entirely on whether you use the "keep my files" option or not. If you do use that your user data files are maintained, but your apps/desktop application programs (formerly just known as installed programs) are not. If you do not use it the Reset is effectively a reinstall by another name.
Refresh: I have never used this feature. From what I can determine from the Microsoft site it is a system restore to "out of the box" condition that uses the recovery partition but that retains your user data files. I doubt I ever will use this feature.
In-Place Update: Again, depends entirely on what option you use. The default is "keep my files & apps" which keeps all your user data files and keeps any apps you've downloaded from the Store and/or desktop application programs you have installed. There can be occasional exceptions if a given desktop app is determined to be incompatible with Windows 10, but I have not had that happen since Version 1511, I believe. You can also choose "keep my files," in which case it behaves much like a standard reset with "keep my files" but instead of reinstalling the current version it updates you to the latest one. Keep nothing (I think that's the wording) makes it act essentially the same as a clean install would, wiping everything.
Brian AKA Bri the Tech Guy (website in my user profile) - Windows 10 Home, 64-Bit, Version 1809, Build 17763
Presenting the willfully ignorant with facts is the very definition of casting pearls before swine.
~ Brian Vogel