Software Subscription management for CSP

[ViberTroka]

As Partners, I'm curious from those who are operating CSP subscriptions, how do you track and renew software subscriptions for your customers? Do you use the API, PartnerCenter PowerShell or some type of 3rd party service or solution?

We do BYOL SQL Server and Windows Server and are looking to revamp how we manage Software Subscription typically interacted with in Partner Center.  

Before I dedicate developer time to craft a solution here I would love to get a pulse on what other Partners are doing.

[umate]

Most partners I know either have their own custom developed solution or use a 3rd party service.

How do you currently manage subscriptions? What parts do you want to change?