Why can't interior design be quoted with a single number? Fee models, the factors that drive cost, what to prepare for an accurate quote and the hidden cost of cheap offers — explained from our project experience in Ankara.
Almost everyone researching interior design starts with the same question: "What will this cost?" It is a fair question — but most of the one-line per-square-metre figures floating around online mislead rather than help. In interior design, price does not come from the service itself; it comes from the conditions of the space and the decisions you make. Two apartments of identical size can finish on completely different budgets.
We will not invent a number for you here. Instead we explain how pricing is actually built — which fee models exist, which factors push cost up, and what you should prepare to receive a sound quote. By the end you will know how to reach a realistic figure for your own project.
Why nobody can quote without seeing the space
An interior architect quoting a rate over the phone is like a doctor prescribing without an examination. Most cost variables only surface on site: the state of existing plumbing and wiring, a wall that cannot come down because it is structural, what the ceiling height allows, building regulations, lift and delivery access, permits, even neighbour constraints.
A remote figure has two possible fates: it is unrealistic and returns later as "additional cost", or it was inflated from the start to cover risk. Neither serves you. That is why a serious studio wants to see the space and listen to you before quoting — this is not a formality but the precondition of a correct price.
Fee models in interior design
The number is project-specific; the structure is standard. Four models are common, and knowing which suits you makes comparing offers far easier.
1. Consultation / on-site opinion. A limited, one-off service: walking the space, assessing the current layout, guidance on plan alternatives, material and colour direction. Suitable if you will carry out the work yourself or simply need a direction.
2. Fixed design fee. Covers concept design, plan solutions, 3D visualisation and construction drawings (electrical, lighting, joinery details, material specification). You or your chosen contractor build it. Because scope is defined in the contract, the budget is predictable.
3. Per-square-metre design fee. The same service priced in proportion to the size of the space. A practical measure for comparable spaces — but area alone does not describe difficulty; a 100 m² clinic and a 100 m² storage unit do not demand the same work.
4. Turnkey (design + build). Everything from design to fabrication, procurement and site management under one roof. Here the budget has two parts: the design/management fee and the construction-material cost. Its biggest advantage is single-point responsibility and surprises becoming visible at contract stage. We described how this works step by step in our turnkey interior design process article.
The 8 factors that drive cost
1. Existing condition of the space. A newly delivered shell and a 25-year-old apartment do not start from the same point. Renewing electrics and plumbing, stripping floors, correcting walls — invisible work that can consume a large share of the budget before any "design" appears.
2. Scope: where, and how much. Kitchen and bathroom only, or a full renovation? Wet areas are the most expensive square metres in any interior; plumbing, waterproofing and tiling come together. The limit of the scope is the limit of the budget.
3. Material choices. This is where the budget has the widest range. The same design can multiply in cost depending on flooring, stone, timber, fittings and hardware. A good interior architect tells you two things: where saving will never show, and where cutting back will cost more later.
4. Share of bespoke joinery. There is a real difference between off-the-shelf furniture and cabinetry, panelling, worktops and niches designed and made for the space. Bespoke work is how you use space efficiently and build a coherent language — but it means production measured and drawn to the centimetre.
5. Technical infrastructure and hidden work. Lighting scenarios, extra sockets and data lines, HVAC, acoustic measures, smart home systems. Invisible at handover, yet they define comfort entirely. Subjects like interior acoustic insulation are the hardest and costliest to add later — they belong in the project from the start.
6. Function of the space. Homes and commercial spaces do not follow the same rules. Clinics, cafés and shops bring hygiene, fire, escape, ventilation and licensing requirements. These look like one line in a budget but form a serious part of the project.
7. Programme and working conditions. A tight deadline increases shifts and therefore labour. Working in an operating office or an occupied home requires zoning, dust control and out-of-hours work. The answer to "when" directly affects "how much".
8. Decision clarity. The least discussed but most real item: decisions that change mid-project. Every "what if we did it this way" after construction starts grows both programme and cost. A properly structured design process exists precisely to prevent this — decisions are made on paper, before fabrication.
What to prepare for an accurate quote
The quality of a quote is proportional to the quality of the information you give. Bring these and the studio can speak far more precisely:
Space: floor plan if available, approximate area, building age, floor and lift access. Scope: which rooms, is furniture included, who supplies appliances? Use: how many people will live or work there, your habits, what frustrates you most today? Time: a realistic expectation and any fixed date (move-in, opening). Budget range: do share it — budget is not a constraint on design but a compass; with a clear range a studio builds a buildable solution instead of selling a dream.
If you are collecting several offers, compare scope, not numbers. What does each include and exclude? Are visualisation, construction drawings, site supervision, warranty and revision rounds covered? Putting two figures side by side that cover different work is the most common mistake. We collected what to look for in 7 questions to ask when choosing an interior design studio.
The hidden cost of a cheap offer
The lowest figure on the market is usually the most expensive option. The reason is simple: whatever does not fit that figure has either been left out of scope or will be built by cutting quality. Typical outcomes are "that wasn't included" items appearing mid-project, materials needing replacement within two years, details improvised on site because they were never properly drawn, and mistakes nobody owns.
A sound offer shows three signs: scope is written down (including exclusions), payments are tied to stages (no pressure for upfront payment) and change management is defined (how extra work gets priced is agreed in advance). With these in place, a slightly higher figure is buying you predictability.
Frequently Asked Questions
What makes interior design fees vary?
Existing condition, scope, material choices, share of bespoke work, technical infrastructure, function of the space, programme and decision clarity. Two projects of the same area can end on very different budgets.
Does an interior architect only design, or also build?
Both are possible. You can buy design only and build with your own contractor, or choose turnkey where design and construction sit with one party. The fee structure follows that choice.
Can I get a rough price over the phone?
A meaningful range is possible only after discussing the space and scope. Share your floor plan, area and expectations and we can speak far more precisely; a firm quote follows an on-site survey.
If I state my budget, will the price rise to meet it?
With a studio that works properly, the opposite happens. Budget is data that shapes the design; with a clear range, a solution is built to fit it rather than time lost on an unbuildable scheme.
How are payments structured?
In a sound contract, payment follows milestones: signing, design approval, start of fabrication and handover. Pressure for full upfront payment is a warning sign.
Get a clear quote for your project
The right place to learn the number is your space, not the internet. At Kaya + Partners we first visit the space in Ankara and beyond, listen to how you live or work, then prepare an offer with the scope defined in writing — so that what is excluded is as clear as what is included.
Get in touch to discuss your project; if you have a floor plan or a few photographs, the first conversation becomes far more productive. To see how we work, browse our completed projects and our Ankara interior design services.