Enterprise Contracts or Subscription Management, which module should be used for Service Contracts ?

Summary:

Enterprise Contracts or Subscription Management, which module should be used for Service Contracts?

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When a client is having Service contracts where he provides services on Annual billing then which module shoud we implement for them, Is it Enterprise contracts or Subscription management or combination of both ?they don't have Procurement contracts or Sales agreements (part sales), they only have Service agreements/contracts.

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