Evidence before verdict
Public data and user-entered assumptions are kept conceptually separate so a result can be traced back to what changed.
Pick the decision. Understand the method. Open the tool.
TOOOLBOX projects are intentionally narrow. Each one is built around a specific high-cost decision, with its scope and assumptions documented here on the parent site before the interactive workspace.
APTHousing
Apartment Cost Planner
Compare Korean apartment sale, jeonse, and monthly-rent transaction records with financing assumptions and management-cost context.
MOVERelocation
Relocation Cost Comparison
Compare salary, taxes, housing costs, non-housing spending, and long-term cash-flow scenarios before relocating in the United States.
How this catalog works
The calculator is only one layer of the product.
A useful decision tool should explain where its numbers came from and what they do not mean. TOOOLBOX therefore keeps a permanent overview for every live project on the parent domain. Those pages describe the problem the tool is meant to solve, the information a user provides, the outputs produced by the model, and the assumptions that can move the answer.
The overview also links the public or official sources that provide context for the calculation. When an output depends mainly on a user assumption, that is described as an assumption rather than presented as an observed fact. Limitations are part of the documentation, not a footnote added after the result.
The live APT and MOVE workspaces remain on their own focused subdomains because their interfaces and data flows are different. The parent site provides the shared publishing, methodology, source, and navigation layer that connects them.
Visible methodology
Each tool has a parent-domain overview covering inputs, outputs, calculation logic, limitations, sources, and common questions.
Context before interaction
Read how a tool works on TOOOLBOX, then open the live subdomain when you are ready to enter assumptions and run the comparison.