How Interior Designers Charge: Flat Fee, Hourly, Cost-Plus, and Retainer

Hiring an interior designer sounds simple until you ask what it costs, and the answer comes back in four different shapes. One designer quotes an hourly rate. Another names a flat fee. A third asks for a retainer. A fourth talks about cost-plus. Same profession, four very different bills.

Knowing which model a designer uses tells you what you are actually paying for: their hours, a finished outcome, or their access to trade pricing. Here is how each one works, when it fits, and what to watch.

How do interior designers charge for their work?

Interior designers charge one of four ways: hourly, a flat project fee, a retainer that reserves their time, or cost-plus, where they add a percentage to the furniture and materials they source.

Most designers use one primary model and sometimes blend two. A designer might bill hourly for early consulting, then move to cost-plus once purchasing starts. None of the four is inherently better than the others. Each answers a different question about scope, and each puts the risk in a different place.

The useful move is not to hunt for the cheapest rate. Compare what each model delivers for the money, and match it to the size and clarity of the work you have in mind.

What is the difference between hourly, flat fee, and retainer?

Hourly bills for time as it is spent, a flat fee names one price for a defined scope, and a retainer collects money upfront that reserves the designer's time and is drawn down as the work proceeds.

Hourly is billed against an estimate and suits small, defined projects: a paint and furniture plan for one room, a consultation on a layout, a second opinion before you buy. You pay for what you use. The catch is that open-ended projects can run past the estimate, and the meter keeps moving as decisions get revisited.

A flat project fee is one quoted price for a clearly defined scope. It is the easiest model to budget around because you know the number before you start. The catch lives in the word "defined." If the scope grows, so does the fee, and a vague scope at the start invites change orders later.

A retainer is an upfront fee that reserves the designer's time and is drawn down as the work proceeds. It is the usual arrangement for whole-home and multi-room projects, where the work is long and the direction shifts along the way. The retainer keeps you on the designer's calendar and funds the planning that happens before anything is ordered. Read how the retainer is applied, because that varies widely from one studio to the next.

What is a cost-plus or designer markup?

Cost-plus means the designer buys furniture and materials at their trade price and adds a set percentage on top when they bill you, so you are paying for their access to the trade rather than for their hours.

The model is common because it lets a designer earn on the sourcing itself. You get their trade relationships and their eye, and the markup is how they are paid for both. For a project heavy on furniture and custom pieces, cost-plus can feel clean, since there is no separate design invoice arriving alongside the furniture bill.

The catch is transparency. A percentage on top of everything the designer buys can be hard to see clearly, and it grows as the project grows. Before you sign, ask what the percentage is, what it applies to, and whether it stacks on top of any other fee. A model you understand is always safer than a model that sounds simple.

How does Seville Home charge for design?

At Seville Home, the first design consultation is complimentary, and for deeper work a design retainer applies that credits toward your purchase, with no cost-plus markup layered on top.

The first consultation, in the Leawood showroom or in your home, carries no cost and no obligation. A designer walks your space, listens to what you are trying to solve, and gives you a real sense of direction. Many projects find their footing right there. For homeowners who want a designer to carry the full project, a design retainer applies, and it credits toward the furniture and pieces you buy.

Two things set the approach apart. There is no cost-plus markup added on top of the furniture, so the design work does not quietly inflate the price of every piece you source. And because the retainer credits back toward your purchase, the design comes with the furniture you were already planning to buy, rather than sitting on top of it as a separate expense. For the mechanics of how that credit works, see our guide on how a design retainer credits toward your furniture. For real numbers, see what full-service interior design costs in Kansas City.

One note on fit. Seville Home's design service is built for homeowners who do not already have a designer. If you are working with one, our trade program supports that relationship instead.

Ready to see what your project would take?

The clearest way to understand what design will cost for your home is to start with a complimentary consultation, no obligation.

A designer from Seville Home can meet you in the Leawood showroom at 5205 W 135th Street, open Monday through Saturday from 10 to 5, or make a house call across the Kansas City metro, from Overland Park and Prairie Village to Mission Hills, Olathe, and beyond. You will leave with a plan and a straight answer on scope.

Book your complimentary consultation and we will take it from there. If you are still weighing the decision, our guide on whether an interior designer is worth it is a good next read.