Illustrative cost

£18,000 to £57,000 ex VAT

Typical
£31,000
Duration
About 10 weeks
Effort
41.5 to 74 days

Illustrative estimate, not a quote. Real prices vary.

Worked out from UK freelance contractor day rates in job adverts, with no consultancy or agency margin added. Consultancies and agencies usually charge more.

Source: IT Jobs Watch. Rates read on ; costs computed on .

What is included

  • Ingestion of agreed document collections
  • Retrieval-augmented generation with citations to the source document
  • Permissions that mirror the document store
  • An evaluation set and accuracy testing
  • Pilot with one team, then rollout

Deliverables

  • A working assistant for the pilot group
  • Evaluation results
  • Runbook and admin guide
  • Rollout plan

Assumptions

  • Documents are in one or two stores (for example SharePoint or Google Drive)
  • The client provides the model subscription
  • A pilot group of 10 to 30 users

Not included

  • Scanning paper records
  • Answers to customers
  • Model and hosting fees

Project plan

Phases run one after another, about 10 weeks in all.

Phases, their length and main tasks
PhaseWeeksMain tasks
Discovery1Choose collections and users; Permissions review; Agree success measures
Data preparation and ingestion3Connect sources; Clean and chunk documents; Index
Build4Retrieval tuning; Prompting and citations; User interface and sign-in
Evaluation1Build the test question set; Measure accuracy and refusals
Pilot and rollout1Pilot training; Feedback fixes; Rollout plan

Who does the work

Person-days per role in each phase, low and high effort.

Days by phase and role
PhaseRoleDays (low to high)
DiscoveryBusiness analyst3.5 to 5.5 days
DiscoveryAI architect2 to 3.5 days
Data preparation and ingestionData engineer5.5 to 11 days
Data preparation and ingestionGenerative AI (LLM) engineer3.5 to 5.5 days
BuildGenerative AI (LLM) engineer11 to 21.5 days
BuildAI engineer3.5 to 7 days
EvaluationGenerative AI (LLM) engineer3.5 to 5.5 days
EvaluationTest engineer3.5 to 5.5 days
Pilot and rolloutProject manager3.5 to 5.5 days
Pilot and rolloutChange manager2 to 3.5 days

How the cost adds up

Cost by role: low, typical and high, before rounding
RoleLow (days × 25th percentile)Typical (days × median)High (days × 90th percentile)
Business analyst3.5 × £425 = £1,4884.5 × £500 = £2,2505.5 × £662 = £3,641
AI architect2 × £549 = £1,0982.75 × £650 = £1,7883.5 × £850 = £2,975
Data engineer5.5 × £425 = £2,3388.25 × £500 = £4,12511 × £688 = £7,568
Generative AI (LLM) engineer18 × £417 = £7,50725.25 × £543 = £13,71232.5 × £825 = £26,814
AI engineer3.5 × £488 = £1,7085.25 × £589 = £3,0927 × £863 = £6,041
Test engineer3.5 × £350 = £1,2254.5 × £438 = £1,9715.5 × £588 = £3,234
Project manager3.5 × £451 = £1,5794.5 × £540 = £2,4305.5 × £714 = £3,927
Change manager2 × £458 = £9162.75 × £525 = £1,4443.5 × £711 = £2,489
Total, rounded£18,000£31,000£57,000

How these estimates are worked out

Effort: for each phase we estimate how many days each role works, as a low and a high case. These are our estimates for a typical project of this kind, not measured data.

Rates: each role's daily rate comes from UK contract job adverts over the last six months, as published by IT Jobs Watch. These are freelance contractor rates as advertised, not what was paid, and not what a consultancy or agency charges.

Low end: the low-effort days at each role's 25th-percentile rate. We use the 25th percentile, not the 10th, because the lowest effort at the cheapest rates gives a floor few buyers would ever meet.

Typical: the mid-point between low and high effort, at each role's median rate.

High end: the high-effort days at each role's 90th-percentile rate.

Totals are rounded to the nearest £500 below £10,000 and the nearest £1,000 above, and exclude VAT. Phases run one after another.

Not included:

  • Software licences, model and hosting fees
  • Travel and expenses
  • Your own staff's time
  • A consultancy's or agency's margin, overheads and risk

Real prices vary with the supplier, the state of your data and systems, how much of the work your own team does, where the work happens and how much risk the supplier carries. Consultancies and agencies usually charge more than these contractor rates, and a fixed price usually costs more than time and materials because the supplier takes the risk.

Sources

Source: IT Jobs Watch: UK contract job adverts quoting a daily rate, 6 months to 15 November 2026. Each role's page was read on . Published under CC BY-NC-SA 4.0.

Day rate sources, one row per role, read on 15 November 2026
RoleIT Jobs Watch pageRates quoted25th percentileMedian90th percentile
Business analystBusiness Analyst1,394£425£500£662
AI architectArtificial Intelligence Architect148£549£650£850
Data engineerData Engineer1,275£425£500£688
Generative AI (LLM) engineerIT Jobs Watch has no "LLM Engineer" or "Prompt Engineer" title with daily rates; mapped to the closest title, Gen AI Engineer.Gen AI Engineer30£417£543£825
AI engineerArtificial Intelligence Engineer384£488£589£863
Test engineerTest Engineer245£350£438£588
Project managerProject Manager1,226£451£540£714
Change managerChange Manager193£458£525£711

Next steps