Subscribe to download
Admin Sandbox

This addon adds a new gamemode "Admin Sandbox", it is a regular Sandbox mode but it can only be used by a player with admin status and above.

Only admins will be able to open spawn menu and control menu, as well as be able to fly, use toolgun and physgun.
When creating a server you can choose whether players without admin can use physgun.
In console: sbox_physgun [0 - disallow, 1 - allow]

Also you can use ULX to give players admin or take away.
ulx removeuser [nickname] - take away
ulx adduser [nickname] admin - give out

There is one disadvantage, if the player does not have this addon, he will not be able to use spawn menu and control menu.