Powershell manage local users and group, nest domain users with domain group and local computer admins

Hi mates,
few months ago one of my customer told me :
"I need to clean a lot of servers in terms of local administrators group. At the sametime I would like to change the method to manage local administrators.....is it possbile to create one group for each single server so I can manage members from AD ?
And what we can do for the current situation ? Is it possible to clean without creating issue ? "
Effectively there were a lot of external partner's account inside these local groups, additionally there were a lot of internal application guys username
Anyway what I needed to do is well explained inside the script.....so enjoy :




No complications, no tricks, only the essential.
Hope this helps.
See you soon