Sorry, but I sincerely hope you just don’t selfhost Vaultwarden.
Its just a shitty laptop with a slow ass HDD, and who knows how much life its got
I think your main problem is going to be a reliability than security when this is the case. What is your plan for backup? You will be locked out, possibly permanently if you lose Vaultwarden data. Judging by your comments, you really, really don’t want to selfhost password manager of any sort.