Thank you for your quick encouraging answer.
So 2GB SD cards for /Boot (one for each OS)
128GB for OS (One for each OS)
2000GB SSHDD (Hybrid) for all OS (Suse, Win10, WinXP, Qubes) shared
As for the VM, do I need to set it up from start, like for my windows 10 part, I would need a 260GB session, with 4+1 partitions, same as my current installation, /Boot (outside the VM) /System; /temp; /swap /Documents
in VM environment I would have the later 3 as VM partitions.
Last time I used VB on Suse for my XP, was maybe 15 years ago ?
WinXP has DOOM pre-installed ... I want to be able to play again even if just once !