Concepts

Before the how-to, here’s the vocabulary used throughout the app.

Product

A single thing you buy or supply — a bag of cement, a metre of copper pipe, an hour of carpenter’s labour, a day of excavator hire.

Each product has a base unit of measure (UOM) — the unit you ultimately price per (per m, per m², per hour). Products live in your Rate Library and are reused across every project.

Price

A product can have many prices — one per supplier, per effective date. A price records what you actually paid (or were quoted) for a particular pack from a particular supplier on a particular day.

The system stores every price you’ve ever entered, so you keep a full history and can see how a product’s cost has trended over time.

Two numbers per price matter:

• Pack price — what the supplier charges you for the pack (e.g. €45 for a 10 m roll).
• Unit rate — the normalised cost per base UOM (e.g. €4.50/m). This is the number that flows into your estimates.

Rate

A rate is the price-per-unit you charge (or budget) for one line of work in an estimate — e.g. “supply and install 150 mm reinforced slab — €185/m²”.

A rate can be:

• Direct — typed in by hand, or copied from a single product’s unit price.
• Built from an assembly — calculated automatically from a recipe of products + labour + waste. This is the recommended approach because the rate updates as costs change.

Assembly

An assembly is a reusable formula that combines several products into one composite rate. Think of it as a recipe:

150 mm Reinforced Slab (per m²) = 0.15 m³ concrete + 12 kg rebar + 0.05 hr formwork-carpenter + 0.08 hr labourer + 5% waste

You define the assembly once. After that, any time you need a slab rate in any project, you apply the assembly and it computes the rate from current product prices. Update a supplier price and every assembly that uses that product reflects the new cost the next time it’s applied.

Assemblies can use variables — named inputs like {thickness} or {waste_factor} that let one assembly cover many cases. A single Reinforced Slab assembly with a {thickness} variable can produce a 150 mm rate, a 200 mm rate, or a 300 mm rate without you copying it three times.

Takeoff

The act of measuring quantities off a drawing — areas, lengths, counts. A takeoff produces how much of each work item is needed; assemblies (or direct rates) turn that into what it costs.

Estimate

The priced schedule of work for a project — a list of items, each with a description, a quantity, a unit, a rate, and a total.

Some industries call this a bill of quantities, cost plan, or pricing schedule — they all mean the same thing. An estimate is what you send to a client to win the job, and what you compare subcontractor quotes against.

Next: see how these fit together in How it all fits together.