Cost categories
Hidden / underestimated cost
TCO over time
This 2D companion runs the same build-vs-buy, hidden-cost and multi-year cost model as the 3D cost-tower version through a flat bar chart built for reading the numbers rather than orbiting a scene: pick a project size, toggle build-in-house versus buying a vendor platform, switch the hidden-cost layer on or off, and slide the time horizon to watch data, compute, talent, tooling, integration and maintenance costs compound into a real total-cost-of-ownership figure, with a side panel breaking every category down to the dollar and a line chart tracing how the total grows from year 1 to year 5.