When you start looking into interior design costs, it is normal to come across very different figures. The main reason is simple: services offered under the same title often include very different levels of work.
One project may only require space planning, a concept and a set of 3D visuals. Another may also include technical drawings, custom furniture details, material selections and site follow-up.
That is why pricing an interior design project based only on square metres is rarely accurate.
What really matters is what needs to be done in the space and how detailed the project needs to be.
Square metres matter, but they do not tell the whole story
Imagine two apartments that are both 100 m².
In the first one, most of the existing layout remains the same and the project mainly focuses on furniture, materials and a few spatial changes.
In the second one, the kitchen, bathrooms, lighting, built-in furniture and overall layout are redesigned from the ground up.
On paper, both projects are 100 m². In reality, the amount of work is completely different.
For this reason, we look not only at the size of a space but also at its current condition and the amount of intervention required.
Design and implementation are not the same thing
This is one of the most common points of confusion.
An interior design fee is not the same as the cost of renovation or construction.
The design stage is where decisions are made: how the space should function, where furniture should be placed, which materials should be used, how lighting should work and which technical details need to be resolved.
Implementation is the stage where those decisions are physically built.
Furniture production, electrical works, painting, flooring, stone, tiles and other construction items belong to this part of the process.
So when comparing two quotations, looking only at the total figure can be misleading.
A lower-priced proposal may not include 3D visualisation, technical drawings or custom furniture details. It may look more economical at first, but missing services often appear later as additional costs.
3D visuals are not just for presentation
3D visualisation is often seen as a way to make a project look attractive. In practice, its real value is helping both the client and the designer make better decisions before anything is built.
It allows you to see how materials work together, whether furniture is correctly proportioned, how colours interact and whether certain areas of the space feel too empty or too crowded.
This helps reduce changes once construction has already started.
Of course, not every 3D visual requires the same amount of work.
A simple model and a fully developed photorealistic scene with custom furniture, detailed materials and carefully prepared lighting are two very different levels of production. That difference naturally affects the project fee.
Why are technical drawings necessary?
A design can look good in a render and still be difficult to build correctly.
For example, a joiner may understand how a TV unit should look from a visual, but they still need dimensions, material thicknesses, door details and construction information in order to manufacture it accurately.
The same applies to lighting, electrical works, ceilings, flooring and many other parts of a project.
Depending on the scope, a project may include:
- custom furniture drawings,
- electrical and lighting plans,
- ceiling plans,
- flooring layouts,
- interior elevations,
- dimensioned construction drawings.
The more detailed the technical package needs to be, the more work is required during the design process.
How does custom furniture affect the project?
In spaces where standard furniture does not make the best use of the available area, custom-made pieces are often the better option.
Wardrobes, kitchens, TV units, workspaces and storage systems can be designed specifically for the space, which usually results in better use of every centimetre and a more consistent overall look.
But designing custom furniture involves more than drawing something that looks good.
Door openings, shelf dimensions, hinges, runners, material thicknesses, fabrication methods and installation all need to be considered.
As the amount of custom furniture increases, the amount of design development and technical drawing usually increases with it.
Material choices can change the budget significantly
A more expensive material is not automatically a better decision.
The same design can often be achieved at very different price levels by changing materials, finishes or product choices.
The important part is knowing where a higher-quality material genuinely makes a difference and where a more balanced alternative will perform just as well.
For us, this is one of the main responsibilities of good design.
The goal is not simply to increase the budget, but to use it in the right places.
What should you look for in an interior design quotation?
Price will naturally be one of the first things you look at. But if you want to compare proposals properly, it is worth checking exactly what each one includes.
For example:
- Which spaces are included?
- How many 3D visuals will be prepared?
- Are technical drawings included?
- Will custom furniture details be provided?
- How many revisions are included?
- Is material and product selection part of the service?
- Is site supervision included?
- Are construction and fabrication costs quoted separately?
Once these points are clear, it becomes much easier to understand whether a quotation is actually expensive, reasonable or simply missing important services.
Final thoughts
There is no single correct price for an interior design project because every space and every client has different needs.
Before discussing cost, the scope of the project needs to be understood properly.
That is also how we approach projects at Arlitect. We first look at what the space actually requires, which services are genuinely necessary and how detailed the project needs to be. The fee is then shaped around that scope.
If you are not sure what level of service your project requires, you can review our pricing information or contact us and briefly tell us about your project.