The quantities may be measured in number, length, area, volume and weight, while soft landscape elements such as plants and trees are measured by their girth or pot size.

In order to prepare a bill of quantities that is 100% accurate, the design should be complete and a specification finalised.

The bill of quantities is issued to tenderers for them to prepare a price for carrying out the works. The bill of quantities assists tenderers in the calculation of construction costs for their tender, and, as it means all tendering contractors will be pricing the same quantities (rather than taking-off quantities from the drawings and specifications themselves), it also provides a fair and accurate system for tendering.

The contractor tenders against the bill of quantities, stating their price for each item. This priced bill of quantities constitutes the tenderer's offer. As the offer is built up of prescribed items, it is possible to compare both the overall price and individual items directly with other tenderers’ offers, allowing a detailed assessment of which aspects of a tender may offer good or poor value. This information can assist with tender negotiations.

The priced bill of quantities will also:

Assist with the agreement of the contract sum with the successful tenderer.

Provide a schedule of rates assisting with the valuation of variations.

Provide a basis for the valuation of interim payments.

Provide a basis for the preparation of the final account

Traditionally landscape projects are fully-designed prior to a project commencing on site.

The contract documents may include:

Articles of agreement and conditions of contract, for completing as a simple contract (or as a deed).

Contract drawings.

Bills of quantities.

Specifications.

Schedules of work.