What Affects the Cost of an Interior Design Project?

Why does one interior design project cost €3,000 while another costs €20,000?

One of the first questions homeowners ask when planning a renovation is:

“How much does an interior design project cost?”

And it’s a fair question.

But the answer is rarely determined simply by the number of rooms or the size of the property.

The cost of an interior design project depends on what is included in the service, how complex the property is, how much technical documentation is required, how many custom solutions are created, and how much coordination is involved.

A design project is not simply a collection of beautiful 3D images. Behind every finished interior are hundreds of decisions, drawings, specifications and details that determine how your home will function for years.

What determines the cost of an interior design project?

There are several important factors that influence the price of interior design services.

1. The size and complexity of the property

The size of the property is one of the most obvious factors.

A 120 m² apartment and a 400 m² luxury villa require very different levels of planning and documentation.

A larger property usually means:

• more rooms to design
• more furniture and lighting
• more materials and finishes
• more technical drawings
• more suppliers and contractors to coordinate
• more decisions throughout the project

However, square meters alone don’t determine the final price. The complexity of the project matters just as much.

A smaller apartment with extensive custom work can require more design time than a larger property with a straightforward layout.

2. The level of design service

Not every client needs the same type of interior design service.

Some homeowners need help selecting furniture, colors, lighting and finishes.

Others need a complete design project with detailed technical documentation.

Depending on the scope, an interior design project may include:

Space planning and floor plans
Furniture layouts
Lighting plans
Electrical plans
Ceiling plans
Flooring plans
Bathroom and kitchen design
Material and finish selection
Custom furniture design
Bespoke joinery drawings
3D visualizations
Technical documentation
FF&E selection
Supplier coordination

The more comprehensive the service, the more expertise and working hours are required.

3. The number of custom solutions

Custom design is one of the elements that can significantly affect the cost of a project.

A standard furniture package is relatively straightforward.

Designing a bespoke kitchen, built-in wardrobes, custom doors, unique shelving, a sculptural piece of furniture or specially designed lighting requires considerably more work.

Every custom element may involve:

Concept → drawings → material selection → technical details → quotations → production → delivery → installation.

The result can be highly personalized, but the process behind it is much more involved.

4. The amount of coordination required

This is one of the most underestimated parts of an interior design project.

Sometimes the designer’s role is primarily creative.

But in a complex renovation or luxury villa project, the designer may also coordinate with:

Architects
Engineers
Contractors
Kitchen companies
Lighting suppliers
Furniture manufacturers
Stone suppliers
Joinery specialists
Curtain and textile suppliers
Art and accessory suppliers

The more people involved in a project, the more communication and coordination is required to make sure everything works together.

And often, the designer solves problems before the homeowner even knows there was a problem.

5. The experience of the interior designer

You’re not only paying for drawings.

You’re paying for experience, decision-making and problem-solving.

An experienced interior designer has already seen what works — and what doesn’t.

After years of working on residential and luxury projects, a designer can anticipate potential problems, recommend appropriate materials, understand realistic budgets and identify where money is being wasted.

That experience can be particularly valuable during a renovation, where a seemingly small mistake can become an expensive one once construction has started.

How much does an interior design project cost?

There is no single price that applies to every property.

An interior design project can range from a relatively simple consultation or furnishing package to a complete luxury design project involving architectural coordination, technical documentation, bespoke furniture, procurement and site supervision.

This is why comparing two design fees purely by price can be misleading.

€3,000 and €20,000 may sound like completely different offers — but they may also include completely different services.

The better question is not:

“Which designer is cheaper?”

It is:

“What exactly is included in the design fee, and what will I receive at the end of the process?”

Good interior design can save you money

Interestingly, a well-planned design project can often cost far less than the mistakes it prevents.

Changing a furniture choice before production is relatively easy.

Changing it after installation is expensive.

Correcting an electrical position before construction is simple.

Moving it after the walls are finished is another story.

This is why interior design should be considered an investment in the renovation process, not simply an additional expense.

Good design helps you make the right decisions before money is spent on construction, materials and furniture.

Before hiring an interior designer, ask:What services are included in the design fee?
How many drawings and plans will I receive?
Are 3D visualizations included?
Is technical documentation included?
Is furniture selection included?
Are custom furniture drawings included?
Is supplier coordination included?
Is site supervision included?
Is procurement included?
What happens if changes are required during the project?

The answers will tell you much more about the value of a design proposal than the price alone.

The real value of an interior design project

A successful interior design project is not about creating beautiful images.

It is about creating a home that is functional, well-planned, cohesive and built around the way you live.

The design fee reflects the amount of expertise, time, detail and responsibility required to achieve that result.

And sometimes, the most valuable part of hiring an interior designer is not what they create.

It’s the expensive mistakes they help you avoid.