# inventories/main
[local]
localhost     ansible_connection=local      ansible_user=<nope>

[staging]
skyubuntu     ansible_host=192.168.1.71     ansible_user=<nope>


# tasks/common.yml
---
- name: Ensure Aptitude is installed
  apt:
    name: aptitude
    state: latest
    update_cache: yes
    force_apt_get: yes
  become: yes
[…]


# host_vars/localhost/vars.yml
---
ansible_become_password: "{{ vault_ansible_become_password }}"


# host_vars/localhost/vault.yml
---
vault_ansible_become_password: <nope>