The tender goes out, three quotes come back, and one is nearly double another. The first reaction is 'someone is overcharging us'. More often the truth is different: three contractors priced three different projects, because the specification allowed three different readings.
A good technical specification makes quotes comparable and the project predictable. This guide is for facility managers, IT leads and procurement teams preparing a specification for a network, security or audio-visual project.
Why quotes differ so much
Every ambiguity in a specification is a risk for the contractor, and it handles that risk in one of two ways. A cautious contractor prices the risk in — and looks expensive. A bold contractor simply leaves the unclear part out — and looks cheap, until change requests start arriving halfway through the project. Either way the client loses: by overpaying, or by losing control of the budget.
Imagine, for example, a specification that says 'install 40 cameras'. It does not say where recording happens, how long footage must be kept, or who provides poles and power for the outdoor cameras. One contractor includes a recorder (NVR) with enough disks for a month of footage, the poles and PoE switches. Another assumes the recorder and switches already exist. Both quotes say '40 cameras', yet they describe completely different jobs.
What a specification should contain
- Context and objectives: what happens on site, how many people work there, what outcome you expect
- Site information: floor plans, ceiling and wall types, existing infrastructure, installation constraints
- Scope by system, with quantities — network outlets, cameras, doors, rooms
- Functional and performance requirements — what the system must be able to do
- Standards, testing and acceptance criteria
- Interfaces and responsibility boundaries with other contractors
- Schedule, working hours and site access conditions
- Deliverables: documentation, training and warranty terms
Describe outcomes, not just products
The most common mistake is a specification that is nothing more than a list of models. It does not say what problem the system solves, and it gives the contractor no room to propose a better or more efficient solution. It is better to state requirements as outcomes and add minimum technical parameters where they matter.
- CCTV: 'an image sufficient to identify a face at the entrance, day and night' — not just '4MP camera'
- Wi-Fi: coverage and capacity requirements per zone, with the expected number of devices — not just a count of access points
- Cabling: category (e.g. Cat 6A), a maximum permanent link length of 90 m, and every link tested with a certification tester
- Meeting room: room size, number of participants, platform (e.g. Microsoft Teams Rooms or Zoom Rooms) and speech intelligibility requirements
Written this way, a requirement becomes testable: at handover you can check whether the outcome has been achieved. The approach applies equally to network infrastructure, video surveillance and access control and meeting room systems.
Responsibility boundaries: who does what
The biggest differences between quotes are often not in the system itself but in the work around it. State explicitly who is responsible for each of the following:
- Power supply for equipment and the server rack
- Drilling through walls and slabs, opening and reinstating ceilings, fire-stopping of penetrations
- Cable containment — trunking and trays
- Coordination with the internet service provider
- Software licenses and their term
- Configuration of the network, firewall and other existing systems
- Removal and disposal of old equipment
Acceptance criteria and deliverables
Define in advance when the work will be considered complete: which tests are performed, who witnesses them and in what form results are delivered. Ask for cable test reports, the labeling scheme, as-built drawings, device configuration backups, secure handover of credentials and staff training. Tie the final payment to documented acceptance, not merely to the end of installation.
The pricing format is part of the specification
If every contractor prices in their own format, comparison will take days. Attach a bill of quantities (BOQ) template with identical line items and ask for: unit prices, materials and labour shown separately, options priced separately, and an explicit list of assumptions and exclusions. That way the differences show up line by line.
Before you send it: a final check
- Offer a site visit to all bidders on equal terms
- Set a clarification period and share the answers with every bidder
- Check that quantities match the drawings
- Mark which requirements are mandatory and which are desirable
- State the evaluation criteria — price only, or price and technical quality
- Give contractors enough time to prepare a proper proposal
Preparing a specification for a new site or a system upgrade? Write to us — we can help you frame the scope and requirements so that the quotes you receive can actually be compared.