What You Can Do By The End

• List all cost drivers
• Estimate token and licence cost
• Measure time saved against a baseline
• Build a case with ranges
• Set up FinOps controls

ROI Is A Simple Formula

• ROI = net benefit divided by cost
• The hard part is honest inputs
• Write every assumption down
• Show ranges, not one number

Cost Drivers: One Time And Running

• One time: design, data, integration, review, training
• Running: licences or usage, hosting, monitoring, support
• People: owners, reviewers, champions
• Hidden: rework and duplicated subscriptions

Two Pricing Styles

• Seat licence: fixed fee per user per month
• Usage pricing: pay for what you consume
• Seats suit assistants used by many people
• Usage suits workflows and agents

What Is A Token

• A token is a small piece of text
• Input tokens are what you send
• Output tokens are what the model writes
• Output often costs more than input
• Prices differ by model and change over time

Estimate Monthly Token Cost

• Count everything you send, not only the question
• Instructions, documents and history count as input
• Agents multiply calls per task
• Use a small model for simple steps

requests_per_month = 20000
input_tokens   = 3000   # question + policy text
output_tokens  = 400
# prices are placeholders: read your vendor list
in_price  = 0.000003    # per input token
out_price = 0.000015    # per output token
cost = requests_per_month * (input_tokens*in_price + output_tokens*out_price)
print(round(cost, 2))

Measure Time Saved Against A Baseline

• Same task, comparable people, with and without
• Count the whole task including checking and fixing
• Include cases where the tool failed
• Self reports are a start, not proof

Case: Faster In The Mind, Slower On The Clock

• Randomised study with experienced developers
• They expected a speedup and believed they got one
• Measured tasks took longer with the tools
• Feelings about speed can differ from measured speed

Saved Time Must Turn Into Something

• More cases handled
• Faster response to customers
• Less overtime or contractor spend
• Work not hired for
• Say which kind of benefit you claim

Benefits Beyond Time

• Quality: fewer errors
• Speed: shorter waits
• Capacity: handle peaks
• Risk: earlier detection
• Value only what you can justify

Build The Case With Three Scenarios

• One table: costs and benefits by year
• Show payback time in months
• Run a sensitivity check
• Adoption is often the biggest lever

FinOps For AI

• Tag every workload by team and use case
• Budget and alerts for each use case
• Monthly review with the product owner
• Quarterly licence review, remove unused seats

Track Unit Cost

• Total spend rises when a tool succeeds
• Unit cost: cost per ticket or per invoice
• Falling unit cost means rising efficiency
• Use the smallest model that passes evaluation

Recap

• Count one time, running and people costs
• Estimate tokens with a formula and real prices
• Measure the whole task against a baseline
• Present ranges and payback time
• Tag, budget, alert and review

Next Week: The Operating Model

• AI council and center of excellence
• Roles, policies and vendor management

Questions And Exercise

• Build a three scenario case for one use case
• Name your most sensitive assumption
• Bring the table to week 10