Sources and assumptions
Every cost, price and benchmark in this guide carries a marker like S1. This page says where each one came from, when it was checked, and whether it is a published figure, derived from published figures, or an estimate you should replace with your own numbers.
- Published Taken from the vendor's or authority's own page on the date shown. Safe to repeat to a customer, with the date.
- Derived Arithmetic on published figures (a median, a conversion, a per-worker split). Show the working if challenged.
- Estimate / Assumption A reasoned guess. Do not quote it to a customer as fact. Replace it with a measured number as soon as you have one.
| Ref | Figure | What it says | Type | Source | Checked |
|---|---|---|---|---|---|
| S1 | Twilio Verify price | $0.05 per successful verification, plus the SMS channel fee. | Published | link | 28 Aug 2026 |
| S2 | Twilio UK SMS price | $0.056 per outbound SMS segment to UK mobiles (alphanumeric sender). UK channel fee for Verify not itemised: the £0.106 all-in figure per login is verification + one SMS segment. | Published (all-in is derived) | link | 28 Aug 2026 |
| S3 | Mux video pricing | Plus tier: $0.025 per minute encoded (720p); storage $0.0024 per minute per month; delivery $0.0008 per minute after 100,000 free minutes a month; on-demand auto-captions free. No minimum commitment. | Published | link | 28 Aug 2026 |
| S4 | OpenAI translation model price | gpt-5.6-luna (the model configured in TeamTalk): $0.20 per 1M input tokens, $1.20 per 1M output tokens. A 300-word post is roughly 400 tokens in and 500 out per language. | Published | link | 27 Aug 2026 |
| S5 | AWS EC2 on-demand prices | t4g.medium $0.0336/h (≈ $25/month), t4g.large $0.0672/h (≈ $49/month), Linux, us-east-1; London (eu-west-2) is within a few percent. From the AWS Price List API. | Published (queried) | link | 27 Aug 2026 |
| S6 | Laravel Forge subscription | Hobby/Growth plans in the $12–$19 per month range. Check the current page; the guide uses ≈ £15. | Published; verify | link | 28 Aug 2026 |
| S7 | Exchange rate | USD → GBP at 0.78 throughout. Assumption; re-run the calculator with today's rate. | Assumption | — | 27 Aug 2026 |
| S8 | Cyber Essentials certification fee | IASME sets the basic Cyber Essentials fee by organisation size: from £320 + VAT (micro) to £600 + VAT (250+ staff). Cyber Essentials Plus is priced by the assessor; £1,400–£2,500 is the typical quoted range for a small company. | Published (CE); estimate (Plus) | link | 28 Aug 2026 |
| S9 | ICO data protection fee | Tier 1 (micro organisations): £52 a year, £47 by direct debit. | Published | link | 28 Aug 2026 |
| S10 | Insurance (public liability + professional indemnity) | £300–£900 a year for a software microbusiness with £1m–£5m PL and £1m PI. Typical broker quotes; get three. | Estimate | — | Aug 2026 |
| S11 | Legal drafting | £500–£2,000 for a solicitor to review a DPA, terms and an order form built from templates. Typical fixed-fee quotes. | Estimate | — | Aug 2026 |
| S12 | Blink pricing | Core £2.95 and Pro £3.75 per user per month, no minimum; reporting and data export is a paid add-on on every tier. | Published | link | 28 Aug 2026 |
| S13 | Workvivo, Staffbase, Microsoft, Slack, Flip, Oneteam, Connecteam, Speakap, Mitti prices | Taken from each vendor's own pricing page or published contract data; every figure and URL is in the competitor research appendix. | Published (see appendix) | link | 28 Aug 2026 |
| S14 | Category median price (≈ £2.75 per user per month) | Median of the published per-user prices in the competitor research, converted at 0.78. | Derived | link | 28 Aug 2026 |
| S15 | Non-English-speaking operatives: 34% average, up to 75% | University of Reading / RICS 2026 study of UK construction sites; ONS: 40% of London's construction-of-buildings workforce is non-UK national. Cited in the competitor research. | Published (see appendix) | link | 28 Aug 2026 |
| S16 | Sales lead times | Sales cycles by buyer type (small builder 3–5 months first touch to revenue; plc division 5–9; group 9–18; single-contract caterer 4–7) and procurement lead times. Reasoned estimates from UK B2B practice; no published benchmark exists for this vertical and deal size; not measured for TeamTalk yet. Replace with your own numbers after ten deals. | Estimate | — | Aug 2026 |
| S17 | Revenue scenarios | Built from the price list applied to the three warm leads plus an assumed win rate on outbound (base: one new logo a month from month 5 at ≈ £450 MRR). Assumptions, not forecasts; the calculator inputs are on the Costs page. | Assumption | — | Aug 2026 |
| S18 | Pipeline benchmarks (reply rates, conversion) | Warm-intro reply 60%+, cold reply 8–15%, pilot-to-paid 50%+ are targets set from general B2B SaaS outbound benchmarks, not TeamTalk data. Treat as starting targets and replace with measured rates by month 3. | Estimate | — | Aug 2026 |
| S19 | Stripe UK card fees | 1.5% + 20p for standard UK cards. | Published | link | 28 Aug 2026 |
| S20 | Usage assumptions in the cost model | 8 posts a month, 3 languages per site, 20% of posts with a 2-minute video, one SMS login per worker per month (30-day sessions), push for everything else. Chosen to be typical of a construction site; the calculator lets you change every one. | Assumption | — | Aug 2026 |
How this guide was made
Who wrote it. Simon Minton, with Claude (Anthropic's AI) doing the research legwork and drafting, on 27–28 August 2026. Simon set the direction and reviewed it; the AI fetched pricing pages, Companies House records and company sites, and wrote the first draft of every chapter. Treat it as a well-researched briefing from a colleague, not as gospel.
What is solid. The description of the product (read from the code itself). Competitor prices and features (fetched from each vendor's own pages, dated). Unit costs for SMS, video and translation (vendor price lists, dated). The 100 target companies (each checked against Companies House or the company's own site, with a source link per row). Certification and ICO fees (published price lists).
What is judgement. The price list is a recommendation, argued in Chapter 3, not a market fact. The revenue scenarios are arithmetic on assumptions, clearly labelled. Lead times and reply rates are estimates from general UK B2B practice, not measured for TeamTalk, and the guide says so wherever they appear.
What we could not verify. Live web search ran out part-way through the target research, so 49 headcount cells in the 100-target list are marked UNVERIFIED and rest on private accounts. Multilingual workforce is published evidence for food manufacturing and care (visa sponsor registers); for construction, catering and facilities it is inferred and marked Likely. Twilio's UK channel fee for verification codes is not itemised on its page; the all-in login cost is derived. The commercial research on sales cycles is still being finalised and will replace the estimates in Chapter 5 when it lands.
What it is not. Legal advice (the DPA and CDM sections tell you what to ask a solicitor and your HSEQ contacts), a forecast (the scenarios are targets you can aim at), or a substitute for the first three conversations, which will correct it.
Numbers you should measure yourself, in order
- Your real cost per login from the first Twilio invoice (replaces S1/S2 arithmetic).
- Confirmed-reach and activation rates from the first two customers (they become your sales numbers).
- Days from first meeting to signature, per deal (replaces S16).
- Reply rates by sector from the first 60 outreach emails (replaces S18).