How to calculate or estimate cost per user on Azure Application (SaaS)?
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I believe there is no magic formula to get to a precise number and probably it will depend on a series of different aspects of the application and users.

But here is the thing:

I'm building a software that will allow churches to manage their members, staff and donations. Think of it as a CRM (or anything close to that). Also we have to keep in mind that some churches has 200 members, others 6000 members. Some churches can receive a few dozen donations month, other thousands of donations month.

It will be a SaaS hosted on Azure. Each church will pay a monthly fee for an account and here is where I got stuck. How do I know the costs so I can decide for a final price?

I'd like to know if someone out there can share some data that will help me estimate:

1) The minimum monthly cost to keep this application running (let's say, with a single church).
2) The projected/estimated cost for each church so we can calculate the final prices.
