kind of..
a "AMD GX-420GI SOC: quad-core APU" the one with no L3 Cache, in an Thin Client and 8Gb Ram. old Laptop ssd for Storage (128GB)
Nextcloud is usable but not fast.
Yes, a g4 or g5 i think, had to fix 5 Capacitors, did a good job at 4, the 5th i had to extend with some wire, not ideal. It boots but USB is not recognized / i asume it does not get enough power. I have a Note on my Phone homescreen to "fix the imac (again)" since June
For banking apps: my Bank only has them as 2fa, if you say you don't have a Smartphone, and give you the same Programm as Windows App eventually, runs great in a win10 VM, the payments are made in there Webportal
Have an fan pushing out on the ceiling in the middle of the house would work good, it will get the hottest air out. But also keep in mind: the air has to come from somewhere, if the house is sealed (new windows) this will not work well.
My laptop will not allow my to login via GUI since upgrade to fedora 41/GNOME?/mutter47. Works with a New account. I have jet to fix it