GuideFormendi team

How to build an interior design project budget

A useful interior project budget makes the next decision easier: what can be specified, what is ready to order and what still needs a price. Start with a clear scope, then keep the figures connected as the design develops.

Apartment plan and finish samples arranged on an oak studio table

Agree what the budget covers

Before choosing finishes, agree with the client which parts of the project you are managing. Design fees, building work, fitted furniture, loose furniture, lighting and delivery may sit in different contracts. Record who pays for each part and which items the client buys directly.

Write down the spending limit, the rooms included and any important exclusions. Confirm whether the figures include VAT and how unconfirmed tax treatment is shown. A budget with a clear scope is easier to discuss than a single total whose contents everyone interprets differently.

Break the work into rooms and packages

Use rooms or zones to make the project recognisable, then group related costs: preparation, finishes, joinery, electrical work, furniture and installation. Choose a structure that helps you find a decision quickly. Avoid recording the same fitted item under both furniture and building work.

Where quantities matter, keep the quantity, unit and rate together. Include the less visible costs that belong to the purchase, such as delivery, installation or removal. A sample price is not necessarily the price for the finished, installed item.

  • Give each item a clear description, location and responsible person.
  • Record the quote date, supplier and what the price includes.
  • Keep unpriced work visible rather than entering zero.
  • Show any reserve separately so it does not hide missing estimates.

Keep the agreed plan beside the current forecast

Once the scope and figures are agreed, save that version as the original budget. Keep later changes traceable instead of quietly overwriting it. You can then explain whether a difference comes from a new finish, extra work or a changed quantity.

The current forecast should bring together recorded costs, the outstanding part of supplier orders and estimated work still to come, without counting the same item twice. For an illustrative package, €4,000 of recorded costs, €3,000 still outstanding on orders and €5,000 of other remaining work gives a €12,000 forecast. An additional €2,000 payment towards an already recorded bill changes the amount unpaid, not the project cost. These are example figures, not market prices.

Make a short budget review part of the project

Before the next order or client meeting, review new costs, outstanding orders, decisions awaiting approval and work that is still unpriced. Check the dates as well: a cheaper alternative may have a delivery time that changes the programme.

Formendi brings the working budget, supplier orders, recorded costs and project changes together. You can start with your own budget or review an imported calculator estimate, then prepare a client report from the appropriate template. Use the sample project to see how the information fits together before requesting beta access.