These are the list of plugins you must have install in the wordpress site.
1. WordPress SEO by Yoast
2. BackupBuddy
3. W3 Total Cache
4. WPForms
5. OptinMonster
6. Edit Flow
7. Soliloquy
8. Sucuri
9. Floating Social Bar
10. Disqus
11. Login Lockdown
12. WP Mail SMTP
13. Advanced Custom Fields
14. Contact form 7
15. Black Studio TinyMCE widget (https://wordpress.org/plugins/black-studio-tinymce-widget/ )
16. Redirection
17. Revolution Slider
18. Royal Slider
19. The Events Calendar
20.