# Compare complete operating costs

Taiga Learning · Worksheet
https://taiga.training/en/lessons/total-cost/

Use fictional or approved information. Do not put secrets in this worksheet.

## Learning objectives
- Compare build and buy options with the same scope and period.
- Include work retained after purchasing a service.
- Explain how sensitive assumptions can reverse a cost comparison.

## Exercise
Open the cost calculator. Calculate the default three-year example. Increase retained work from 1.0 to 1.5 people and subscription cost from €120,000 to €150,000. Explain why the lower-cost option changes. Add three costs that the simple calculator does not include.

## Your response
- Scenario and scope:
- Assumptions and open questions:
- Proposed answer or decision, with reasons:

## Verify your response
| Claim or criterion | Evidence or test | Result or gap | Owner |
| --- | --- | --- | --- |
| | | | |
| | | | |
| | | | |

## Next action
- Action, owner, and date:
- When will you review this response?

## Principle to retain
Compare the cost of a complete operating model. Include retained work and test uncertain assumptions before treating the result as a decision.

## Sources
- [FinOps Foundation: Framework](https://www.finops.org/framework/)
- [CNCF: Platforms White Paper](https://tag-app-delivery.cncf.io/whitepapers/platforms/)

This worksheet supports learning. Completing it does not itself authorize a production change.