Declare the inputs
Separate user assumptions from public records so a changed result can be explained.
TOOOLBOX / PRACTICAL DECISION TOOLS
Tools for expensive decisions.
Compare housing, relocation, and weekend fishing options with the inputs, calculations, public evidence, and uncertainty kept visible.
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- live tools
- 24
- worked analyses
Our tools
Focused tools. One decision at a time.
View all tools →Each workspace is paired with documentation explaining its inputs, outputs, data sources, method, and reliability boundary.
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.
FINVECTOROutdoors
Weekend Fishing Intelligence
Prioritize U.S. fishing waters with official stocking evidence, hydrology, weather, terrain, access, connectivity, and species habitat context.
Current tool network: APT + MOVE + FINVECTOR. Public evidence and user assumptions remain separate throughout the calculation.
Review the source register →Built around the decision
A result you can inspect and challenge.
Show the calculation
Expose intermediate arithmetic and model rules instead of asking readers to trust a score.
Keep the limits visible
Treat missing evidence as unknown and state what the tool cannot decide.
Worked decision notes
See the reasoning, not only the result.
Twenty-four reviewed cases combine declared inputs, official data snapshots, intermediate calculations, sensitivity, and owner-authorized verification records.
APT · CASE 01
From an ₩800M price to a monthly housing burden
A reproducible mortgage example that separates transaction evidence, financing assumptions, and costs the calculator cannot know.
Inputs · calculation · sensitivity · sourcesAPT · CASE 02How 3.5% versus 5.0% changes the same loan
A rate sensitivity check for a fixed ₩480M principal and 30-year equal-payment schedule.
Inputs · calculation · sensitivity · sourcesAPT · CASE 03Buy versus jeonse: compare the financing layer honestly
A deliberately limited comparison showing why principal repayment and interest-only deposit financing should not be labelled as equivalent monthly costs.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 04Why a $25K raise can create only $784 of monthly room
A transparent before-tax screen showing how rent and other spending absorb a larger gross salary.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 05Calculate a relocation salary floor before tax
A simple break-even floor that preserves current pre-tax room before a more personal tax model is applied.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 06When does a $12K move pay back?
A recovery-period calculation that tests whether a monthly improvement is large enough to offset one-time moving costs.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 07A stocking week is not a stocking day
An evidence-classification example showing why published date precision must survive the ranking pipeline.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 08Missing access data should not become a zero
A ranking example that distinguishes unknown evidence from negative evidence and shows the reweighting arithmetic.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 09A nearby gauge is a proxy, not the fishing reach
A hydrology interpretation case that prevents geographic proximity from becoming false measurement certainty.
Inputs · calculation · sensitivity · sourcesAPT · CASE 10The September 2026 fixed-rate term trade-off
A ₩300M loan stress test using HF's published September 2026 endpoint rates: 4.90% for 10 years and 5.20% for 50 years.
Inputs · calculation · sensitivity · sourcesAPT · CASE 11What a full 1-point HF discount changes
The same ₩300M principal is tested at HF's September 2026 base and maximum-discount endpoint rates.
Inputs · calculation · sensitivity · sourcesAPT · CASE 12Use the official rate range as a stress band
A 30-year planning model tests 4.90% and 5.20% as an explicit range informed by HF's September endpoints, not as quoted 30-year products.
Inputs · calculation · sensitivity · sourcesAPT · CASE 13A cancelled transaction must leave the price baseline
A controlled six-record audit applies MOLIT's official cancellation status before calculating a comparable-price median.
Inputs · calculation · sensitivity · sourcesAPT · CASE 14Normalize area before comparing two sale records
A transaction-field audit shows why raw prices for 59.9㎡ and 84.9㎡ homes cannot be ranked without an area-normalized view.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 15The 2026 filing-status deduction gap
IRS-published 2026 standard deductions are translated into taxable-income differences before any city comparison is attempted.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 16Federal tax absorbs part of a $25K raise
A 2026 single-filer example applies the IRS standard deduction and marginal brackets to $100K and $125K salaries.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 17The 2026 Social Security wage-cap threshold
SSA's $184,500 taxable maximum creates a visible payroll-tax threshold that a relocation model must not smooth away.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 18$100K does not buy the same regional basket
BEA's 2024 regional price parities turn the same nominal salary into a price-level-adjusted comparison for California and Arkansas.
Inputs · calculation · sensitivity · sourcesMOVE · CASE 19A national labor headline is not a destination verdict
BLS's July 2026 metro release is decomposed into higher, lower, and unchanged year-over-year unemployment-rate groups.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 20A 2.87-foot reading needs its timestamp
A live USGS Little Falls snapshot is converted into an observation-age gate instead of being shown as an untimed condition claim.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 21California's seven-day plant window is not an event day
CDFW's 2026 schedule is used to preserve a seven-day range for Kern River Section 5 rather than invent a precise stocking date.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 22Read the Ischua Creek stocking mix without overclaiming
NYSDEC's 2026 plan for 3,867 nine-inch and 430 twelve-inch trout is converted into a transparent size mix and density context.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 23Planned stocking and actual stocking are different datasets
New York's current-season plan and its actual stocking archive are treated as separate evidence classes before a freshness score is calculated.
Inputs · calculation · sensitivity · sourcesFINVECTOR · CASE 24A forecast card needs a data-lineage trail
The National Weather Service linked-data workflow is translated into a four-step lineage from coordinates to office, grid, hourly forecast, and alerts.
Inputs · calculation · sensitivity · sourcesPublishing standard
Tools first. Claims still need boundaries.
Calculators are more useful when ownership, data sources, assumptions, limitations, and corrections remain visible.
TOOOLBOX Publisher
The owner and developer responsible for the TOOOLBOX calculation tools, data-source registry, worked examples, corrections, and publication decisions.
Reproduce before publishing
Each indexed case is checked for reproducible arithmetic, official-source fit, explicit assumptions, sensitivity, and a clear boundary on what the result cannot prove.
No sponsored rankings
TOOOLBOX does not sell placement in its calculations or publish sponsored rankings disguised as tool results.
See what changed and why. The public review log records calculation checks, source changes, corrections, and pages intentionally withheld from search.
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