Cost calculator · 10 MIN
Compare build and buy costs
Include setup, operation, and retained engineering work. Change the assumptions and compare the result.
The situation
You lead a fictional engineering team. It needs an AI delivery platform with access controls, CI integration, reviews, and operational support. Compare building and maintaining that platform with buying a service that meets the same requirements.
What to do
- Select Original estimate. Compare the three-year totals, including the work your team keeps when it buys.
- Select More retained work. See what changes when buying still needs two people. Then edit the fields to test another assumption.
Start with an example
Each example fills the fields below and shows the result. You can then change the values yourself.
Compare two options with the same scope. The default amounts are fictional. They are not Taiga prices or typical market costs.
One full-time equivalent (FTE) means one person working full time for a year. A value of 0.5 means half that capacity. Annual person cost includes salary and employer costs. Other annual costs can include cloud and model services.
Costs for the selected period
Compare another example · Edit these values
| Cost | Build | Buy |
|---|---|---|
| Setup | ||
| Ongoing, per year | ||
Formula: setup + years × (people × annual person cost + other annual costs + subscription, if applicable). The calculation excludes interest, tax, inflation, transition delays, and exit costs.
Test your assumptions
Increase retained work by 0.5 full-time equivalents. Then change the subscription cost by 25%. Identify which assumptions change the conclusion.
A lower calculated cost does not establish suitability. Assess security, responsibilities, delivery capability, and exit options separately.
TO FINISH
Why can buying become more expensive even when the subscription price stays the same?
Compare your answer with the explanation
Buying does not remove all internal work. In this example, one extra full-time person adds €360,000 over three years. The buying total rises from €870,000 to €1,230,000. Building stays at €1,080,000. These fictional assumptions reverse the cost comparison; they do not establish which option meets your requirements.
Use this at work
Ask a supplier which integration, security, and operational tasks your own team must still perform.
Choose another exercise