KB

Case study

Leasing Calculator — business leasing estimate tool

Business calculator demo for quick indicative leasing cost estimates before a finance offer conversation.

Leasing calculator business tool preview

Problem

Business users often need a fast leasing cost estimate before they are ready for a formal financial offer.

Goal

Build a calculator that handles common leasing inputs, displays a clear result summary and can capture a lead.

Status

Production-like business tool demo

Stack

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Key features

  • Asset type, net/gross value and VAT conversion.
  • Down payment, leasing period, buyout and annual rate inputs.
  • Simplified insurance, GAP and service estimates.
  • Monthly net/gross rate, financed amount, installments and financing cost summary.
  • Scenario presets, print/save-friendly result and lead endpoint.

Technical decisions

  • Calculation logic lives outside UI components so it can be tested directly.
  • The formula uses a simplified annuity calculation for indicative estimates.
  • The UI includes a financial disclaimer instead of presenting results as an offer.

What I learned

  • Separating business calculation logic from interface state.
  • Designing a result summary for a practical business workflow.
  • Writing responsible copy for indicative financial values.

Next improvements

  • Add more edge-case tests for calculation scenarios.
  • Improve lead persistence beyond webhook forwarding.
  • Add analytics for calculator usage.
  • Improve accessibility of controls.

Limitations

The calculator is informational and simplified. It is not a financial offer and results may differ from real leasing proposals.