Thanks for all the suggestions. I still have to try Inventree.. I don't need the paid phone app, because I've a lab PC right next to storage.
I won't be using a MS access application. Personally I don't even have the MS Office suite anymore, and since I don't run Windows as main OS, don't intend to do so neither.
@HendriXML
The KiCad BOM export tool sounds interesting. I do agree with your comments about Partkeepr. For me the app feels like an overbuilt tech demo that never received enough attention to mature into a stable and dependable application. I really want to rid it out of my toolbox because it has been so unreliable. I've got faulty server starts once a month when I update and reboot my Docker VM, and on other occassions I have been unable to logon the web interface even though I was using the correct user credentials (the GUI also rarely triggers the credentials remember prompt in FF - something for an intranet tool that IMO doesn't even need a login page, would be quite handy if it worked...).
In my view the basis of an inventory management system should mostly be specification management. Those should be created with ease and with inheritance of data and without unneeded redundancy. Those should searchable using different parameters. On those entities (designed) components could then be added. On designed components physical components could be added, those have an amount, price, location.
Well that's what I run for Altium (and possibly other CAD tools if I switch) right now. It's a program I wrote 8+ years ago when I had a lot more of my younger energy flowing and just did things, even though time invest/return ratio would be a bit off. This application basically indexes my own Altium library symbols/footprints, tracks info from Octopart and organizes supplier pricing, datasheet and CAD information. I could add project/BOM/inventory stock management, but I'm afraid that will require a lot of maintenance and time to do so.
Also the application is written in C#.NET. Since I design PCBs with Altium in a Win VM, it's fine to use that C# application alongside it. But in the mindset of side-grading to KiCad, and therefore enabling a Linux-only experience, I don't really feel that inclined to invest a lot more devtime in a C# application..
I'll see if I have some time later this week to try out Inventree. This week has been kind of hectic so hadn't been able to get around to it.