DTC website cost comparison: 36-month cash planning worksheet
Prepared 17 October 2026

FILES
dtc-website-cost-worksheet.xlsx: editable Compare quotes and Illustrative GBP sheets.
quote-comparison-template.csv: single-sheet formula fallback with blank quote inputs.
illustrative-gbp-example.csv: the same layout, using invented GBP planning inputs.
expected-results.csv: independent numerical controls for the illustrative inputs.

START WITH YOUR QUOTES
Open the XLSX in a compatible spreadsheet and use Compare quotes. Pale blue cells
are inputs; green cells are formulas. Preserve the formulas and the shared 36-month
period. Formula cells recalculate automatically when supported by your application.
Enter a shared 3-letter currency, monthly orders and average order value in B5:B7.
Complete supplier, currency, source/reference, date and tax basis for both quotes
in B11:B15 and D11:D15. Use YYYY-MM-DD for the date. Record your quote's validity,
renewal dates and payment mix in the source/billing notes or your supporting quote.

Every numeric cost input and its adjacent source/billing note is required. Enter
zero only after checking it, with a note such as 'checked: none' or 'included in
platform'. A blank remains Incomplete. This includes optional costs you confirm
are absent. Enter percentages as 1.5% or 0.015, rather than 1.5. Processing percentage,
processing fixed fee per order and additional platform transaction percentage
are separate inputs. Costs and scenario numbers must be non-negative; monthly
orders must be whole numbers. Invalid input and currency mismatch withhold totals.
The comparison delta is available only when both quotes are Complete and use the
shared currency. There is no FX conversion. Compare scope alongside the cost.

COST BASIS
Enter cash payable including any tax charged, in one currency for the scenario.
Record each quote's tax treatment in its tax-basis field. The sheet does not deduct
VAT or sales tax recovery: assess recoverability separately for your business.
Average order value is the amount charged to a customer, before payment fees.
The assumed orders and average order value stay the same for both quotes.

Enter each cost once. If hosting is included in a platform or support price, put
zero in the separate hosting line and record the bundle. Record initial build,
migration, content and integrations once. Additional platform transaction fees
belong in their own percentage input, rather than in processing percentage too.

Monthly inputs are the agreed cash cost across the full 36 months divided by 36.
Annual inputs are the agreed cash cost across the full 36 months divided by 3.
For a first-year bundle followed by two renewals of 30, enter annual equivalent
20: 0 + 30 + 30 = 60 over the period, then 60 / 3 = 20. Record renewal dates,
promotions, billing changes and rounding in the notes. These are planning inputs,
not a claim that suppliers hold prices fixed for three years.

Payment charges use 36 x monthly orders x average order value x processing rate,
plus 36 x monthly orders x fixed processing fee. Additional platform charges use
the same gross order value x the separate platform rate. This is one assumed mix,
not a full payment-provider tariff model. Use an agreed effective rate or adapt
the model for different cards, countries, FX, refunds, chargebacks or rate tiers.
Add further costs once in the full-period other-allowance line and describe them.
Revenue growth, profit, tax recovery, finance costs, refunds and shipping are not
forecast here; include relevant costs through your documented inputs or separate
planning. The worksheet total is cash cost for its entered scope.

ILLUSTRATIVE GBP CONTROLS
All names, dates, costs and rates in Illustrative GBP are synthetic teaching inputs,
not supplier quotes, Turing prices, market rates or forecasts of your sales.
Both examples assume 36 months, 100 orders/month and GBP 50 average order value:
3,600 orders and GBP 180,000 gross order value.
Quote A: 6,400 initial + 3,600 monthly + 72 annual + 3,600 processing = GBP 13,672.
Quote B: 8,000 initial + 5,040 monthly + 72 annual + 3,600 processing = GBP 16,712.
Extra platform charges and other allowance are checked zero. B minus A = GBP 3,040.
The included hosting in A is checked zero in its separate hosting line.

CSV FALLBACK
Each CSV is one sheet and contains intentional local arithmetic/status formulas.
Import as UTF-8 with comma separators; preserve the five columns and cell positions.
Formula evaluation depends on your spreadsheet's CSV import and locale settings.
Choose formula interpretation if your importer offers it. If it displays formulas
as text, use the XLSX or import with formula support. Currency/date/source text is
metadata. Both actual quote currencies must match the shared scenario currency.

VALIDATION AND LIMITS
The supplied example's numerical controls were checked independently with Python
exact arithmetic. XML structure, formula references, incomplete/zero/mismatch guards,
CSV parity, cached example values and deterministic workbook bytes were checked.
No Excel, LibreOffice or other spreadsheet engine was available or executed for
this release. Cached values in the XLSX are supplied controls, not runtime proof.
Recalculate and check the example totals in your spreadsheet before adapting it.
Input validation can be bypassed by pasting; the formula status also checks inputs.
Source and tax notes document your assumptions; their commercial accuracy remains
for you to check against your quotes. Keep a copy of each dated quote with the file.