Show the source.
Explain the math.

Sources have different roles.

For a published lender process, we use the lender’s own instructions. For a state tax statement, we look to the relevant authority. Regulatory text and official interpretations establish their own scope. Other publishers can help us identify questions but are not a substitute for the underlying rule.

A source about Texas cannot determine another state’s tax treatment. One lessor’s FAQ cannot establish another lessor’s policy. Public instructions cannot verify an individual account’s eligibility, amount or required packet.

What a source-check date means.

A source-check date records when the cited public material was reviewed for a page. It is not necessarily the date a rule became effective, a claim of continuous monitoring, or a statement that a reader’s transaction was reviewed. The initial source check for these guides is September 13, 2026.

When a material source or explanation changes, the affected page should be reassessed and its dates updated to reflect actual work. Dates should not be refreshed simply to make an article look new.

Calculation methods and testing.

The purchase calculation uses integer cents to add separate charges and subtract a separately applicable credit. The financing estimate uses a fixed nominal note rate and equal monthly periods. Interest, loan fees and upfront purchase cash are shown separately. The calculator page includes formulas and a complete worked example.

The implementation includes automated checks for the worked examples, included fees, zero interest, unknown costs, invalid amounts and overpayments. These checks assess the defined mathematical model. They are not a review of your contract or a claim that an actual lender will use the same dates and rounding.

AI assistance and accountability.

AI tools assist with source research, drafting, code and tests. The site identifies David Jung as its accountable publisher. It does not present invented writers, credentials, customer experiences or expert-review badges. A source link and passing test do not replace judgment about whether a claim is supported in context.

Our guides provide general educational information. They have not received a separate licensed financial, tax or legal review.

Examples are examples.

Quote amounts and transactions used for teaching are explicitly hypothetical. They are not real customer records, fee schedules, lending offers, market averages or promises of savings. We do not create arbitrary readership or review counts as evidence of popularity.

Commercial relationships and corrections.

Any active paid arrangement should be identified where it affects the reading experience. Advertising must remain distinguishable from calculators, navigation and download controls. The About page describes the current funding model.

Use Contact and Corrections to report a specific issue. The publisher is responsible for reviewing reported material errors and recording substantive corrections.