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.
How to read the labels
- 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 Do not quote it to a customer as fact.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 (long code or alphanumeric sender; $0.0524 short code). Twilio itemises a Verify channel fee for the US only ($0.0083); for the UK the all-in login cost is the $0.05 verification plus the published $0.056 segment = $0.106 ≈ 8.3p. Verified 28 Aug 2026. | 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 for PL and PI; cyber cover adds £300–£500; budget £1,200 in total. Estimate: get three quotes. | 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% | Tagg & Phua, University of Reading, RICS Built Environment Journal, 30 Mar 2026: a pilot survey of 12 construction and project managers, so treat it as what managers report, not a measured share; ONS gives the harder numbers: 15.7% of UK construction workers (SIC F, including the self-employed) were born outside the UK (APS Oct 2023–Sep 2024, published 26 Feb 2025, ad hoc ref. 2666), and 57.4% of London's construction workforce (Census 2021, a custom cut by industry and country of birth via the ONS Census API; no published table). The 2018 ONS article (40% non-UK national in London construction of buildings) is the historical series. Detail in Chapter 2. | 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; 2.8% + 20p for premium UK cards (Stripe's term, which includes consumer rewards cards, so "commercial card" is the wrong word); Bacs Direct Debit 1%, minimum 20p, capped at £4. | 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, about two phone verifications per worker per year (login policy C: device-bound sessions, re-verify on a new device), push for everything else; policy A (monthly re-verification) is shown alongside as the cost of not shipping C. Chosen to be typical of a construction site; the calculator lets you change every one. | Assumption | — | Aug 2026 |
| S21 | Paid vs free pilots | Paid pilots convert 60–90%; SaaStr describes free pilots as a false milestone about 95% of the time. Detail and links in the commercial research §4.1. | Published (see appendix) | link | 28 Aug 2026 |
| S22 | Discount norms | Observed: 10–15% for annual prepay, 15–25% for a public case study or reference. Commercial research §2.8. | Published (see appendix) | link | 28 Aug 2026 |
| S23 | RDS, Forge Growth, monitoring prices | RDS db.t4g.medium and storage from AWS pricing pages; Forge Growth £13.99; error and uptime monitoring list prices. Commercial research §1.4–1.6. | Published (see appendix) | link | 28 Aug 2026 |
| S24 | Health and safety legislation | HSWA 1974 s.2 and s.40; MHSWR 1999 regs 10 and 12; CDM 2015 regs 13 and 15; HSE migrant-worker guidance. Primary sources on legislation.gov.uk and hse.gov.uk, linked in the commercial research §3.3. | Published (primary) | link | 28 Aug 2026 |
| S25 | Revenue scenarios and cash needs | Funnel: 3 warm leads + 100 targets; conservative 2 tenants (£12,100 ARR), base 4 + 1 expansion (£43,400), upside 7 + 2. Cash need £49k–£64k including founder living costs. Conversion rates are reasoned estimates; arithmetic in the commercial research §5.3–5.4. | Estimate (arithmetic shown) | link | 28 Aug 2026 |
| S26 | Construction shutdown dates | CIJC Working Rule Agreement annual holidays 2026: winter shutdown 18 Dec 2026 – 4 Jan 2027; the industry-wide summer shutdown has been discontinued. | Published | link | 28 Aug 2026 |
| S27 | Sector growth | Contract catering growing ≈ 9.3% a year; private housing output forecast down 10%. Sources in the commercial research §3.6. | Published (see appendix) | link | 28 Aug 2026 |
| S28 | Barratt Redrow procurement | Barratt Redrow centralises ~95% of procurement across ~160 group agreements. Source in the commercial research §3.1. | Published (see appendix) | link | 28 Aug 2026 |
| S29 | The Menu Partnership Ltd | Companies House record (company 13015668), Bicester. | Published | link | 28 Aug 2026 |
| S30 | Employment Rights Act 2025 commencement | Employment Rights Act 2025 (c.36), Royal Assent 18 Dec 2025; s.20 ("all reasonable steps") and s.21 (third-party harassment) commence 30 October 2026 per the Government's Implementing the Plan to Make Work Pay roadmap (the 25 Aug 2026 roadmap update concerned union balloting, not this). The duty in force today is the Worker Protection Act 2023 test, since 26 Oct 2024. Verify before quoting; commencement dates move. | Published; verify | link | 28 Aug 2026 |
| S31 | ICO 'Behind the screens' | ICO report on private messaging at DHSC, 11 July 2022; a reprimand, not a fine. There is no 2024 report. | Published | link | 28 Aug 2026 |
| S32 | PECR and marketing penalties | PECR reg 22 (corporate vs individual subscribers) and reg 23; reg 21 requires screening calls against the TPS/CTPS. From 5 Feb 2026 (DUAA 2025) the ICO's PECR penalty regime aligns with UK GDPR: up to £17.5m or 4% of turnover for the most serious breaches (reg 21/22 marketing rules) and £8.7m or 2% for the lower tier. Commercial research §4.2; ICO enforcement guidance. | Published (see appendix) | link | 28 Aug 2026 |
| S33 | Fair Payment Code | Replaced the Prompt Payment Code. Commercial research §3.5. | Published (see appendix) | link | 28 Aug 2026 |
| S34 | International transfers | Checked on the official DPF list, 28 Aug 2026: Twilio Inc. Active under the UK Extension to the EU–US Data Privacy Framework; Mux Active but re-certification under review; OpenAI not listed, so it needs an IDTA/Addendum and a TRA. Re-check every six months; certifications lapse. UK GDPR Chapter V was rewritten on 5 Feb 2026 (Arts 44A–45C). Commercial research §3.5; legal pack. | Published (see appendix) | link | 28 Aug 2026 |
| S35 | Outbound and retention benchmarks | Saleshandy 2026 (53M emails: 3.7% average reply; lists under 200 prospects 15–20%), Lavender (operations buyers 3.4%, well-written 5.4%), Gong (344 emails per meeting), HubSpot 2025 (21% average win rate), Gartner (buying groups of 6–10), ReferralRock/Marketo (referral leads convert 11%); Simpplr and Microsoft frontline reach statistics; SaaS retention medians by ACV band. All linked in the commercial research §4.1 and §4.9. Treat as directional: several are vendor-published. | Published (see appendix) | link | 28 Aug 2026 |
| S36 | Founder background | Jake Hughes is Founding Partner and Chairman of Hunter Design (Eton/Maidenhead), a place-branding consultancy; its site lists Berkeley Group, The White Company and Hotel Chocolat among brands he has worked on. | Published | link | 28 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 200 target companies, each with a source link per row; about a fifth are tied to a Companies House record and the rest to the company's own site or a public register. 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 remains unverified, precisely. Of 200 target companies, 23 headcounts could not be tied to a filed figure (private companies under the 250-staff reporting threshold, or brands that are not employers) and are marked in the table. 66 companies have no published evidence yet of a multilingual workforce and are marked Likely; 134 are evidenced by a Home Office sponsor licence or a published statement. Twilio publishes a per-country channel fee for US verifications only; the UK all-in login cost ($0.106, about 8.3p) is its verification fee plus the published UK SMS rate. Sales-cycle lengths and funnel conversion rates are estimates until the first deals replace them, and every one is labelled.
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.
The two research reports behind this guide are published in full: competitor research and commercial research, each with its own source list.
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).