PowerShell expert

We are looking for someone who can create a PowerShell script. We currently have following system and want to automate process as much as we can.

We have in-house windows server 2008 R2 active directory
We have in-house Exchange 2010
We have in-house Azure AD server installed on server 2012 R2
We use office 365 for emails

We do get lots of requests regarding users leaving and joining. We currently use manual process to such as:

Remove user from all groups
Disable user
Convert user mailbox into shared mailbox on office 365
Revoke office 365 license (once mailbox is converted to shared mailbox)

We want to create a system where we can just run ONE command or script which all these in one go.

It will be great to have GUI but it is fine if we can achieve this with just script.

Please let me know if you can do this and how long it will take to complete. Please also mention your fixed charges.

Thanks