Vagrant disable Guest Additions

In your Vagrantfile, add the following param

Vagrant.configure("2") do |config|
    ....
    config.vbguest.auto_update = false
    ....
end

Users might not have the vagrant-vbguest plugin, and you could wrap its use in a conditional to avoid confusion.

Vagrant.configure("2") do |config|
  ....
  if Vagrant.has_plugin?("vagrant-vbguest")
    config.vbguest.auto_update = false
  end
  ....
end