Wall & Fifth

Marketplace UX & UI design. Serving two audiences without compromising either.

The interface design challenge of a marketplace is unlike any other product category. Every major design decision — the listing card layout, the search filter system, the trust badge hierarchy, the navigation structure — has to work for a buyer and a seller who have fundamentally different goals, different mental models, and different definitions of a successful visit. Wall & Fifth designs marketplace interfaces that hold that tension without collapsing it.

£3k / month

Starting retainer

3–4 maximum

Clients at any time

12+ internally

Ventures built

No lock-in

Commitment

The dual-audience design problem

Most UX/UI design starts with a single primary user. You identify their goals, their mental model, their pain points, and you design an interface that serves that person as effectively as possible. In a marketplace, that approach produces an interface that works for one side of the market and frustrates the other.

Buyers want discovery — they want to find things they didn't know existed, filter efficiently toward what they want, and trust that the supply they're seeing is real and current. Sellers want visibility — they want their listings to be found, their profile to communicate credibility, and their effort in creating good listings to be rewarded with exposure.

Those goals are not opposed — a marketplace that serves buyers well attracts more buyers, which benefits sellers. But the design decisions that serve each side are often in tension. More information per listing card benefits sellers and creates cognitive load for buyers. Aggressive filtering benefits buyers and can bury seller supply. The design has to navigate that tension intelligently rather than defaulting to one side.

The listing card — where both audiences meet

The listing card is the most commercially important UI element in any marketplace. It appears at every stage of the buyer journey — on the homepage, in search results, in category pages, in saved searches — and it has to communicate enough about the listing to earn a click, without so much information that it overwhelms the browsing experience.

For the buyer, the listing card is a rapid decision surface: is this worth clicking? For the seller, it is the primary representation of their supply. The design has to serve both — pulling the signals most likely to earn buyer engagement while giving sellers' listings the visual real estate their quality deserves.

We design card systems with deliberate information hierarchies — the primary conversion signals (price, condition, location, key attribute) above the fold, secondary signals (seller rating, listing age, availability) in a supporting position, and a visual design that gives well-photographed listings the best possible representation. The system has to handle the full range of inventory quality — from professional listings with twelve images to first-time seller listings with one — without the card system breaking.

Search and filter architecture

Filter design in a marketplace is a balancing act between completeness and usability. Every attribute in the listing data is potentially filterable — and every filter you hide is a buyer who can't find the specific thing they're looking for. But every filter you expose increases the cognitive load of the search experience and reduces the chance that a buyer will engage with any filter at all.

The right architecture exposes the filters that eliminate the most irrelevant inventory for the most buyers — typically price range, category, location, and one or two vertical-specific attributes — and places the rest in a secondary layer accessible to buyers who need that specificity. The visual design of the filter system needs to make the active filter state immediately legible: the buyer should always be able to see, at a glance, what constraints are currently applied and remove any of them individually.

Trust signal design at scale

Trust in a marketplace is communicated through a system of signals that compound across the platform. The challenge is designing those signals to work at scale — when there are thousands of listings from hundreds of sellers, each with different histories and verification levels.

We design trust signal systems that communicate meaningfully at the listing card level (a single badge or indicator), expand at the listing page level (full seller profile, review history, transaction count), and reinforce at the platform level (the overall impression of quality and curation that comes from the visual design and the content standards). Each level has to be designed as part of a coherent system, not as independent decorative elements.

How we work

Interface audit

For existing marketplaces, we review the full interface against both buyer and seller experience goals — identifying where the dual-audience tension is producing friction for one or both sides.

Design system

We build a component system specifically for the marketplace — listing cards with variants, filter components, trust signal components, navigation systems, and the modal and overlay patterns that marketplace interactions typically require. Every component is designed to handle the full range of data states the marketplace will produce.

Handoff and implementation

Complete Figma handoff with all states, variants, and specifications. We can stay involved through the build phase to ensure the implementation matches the design intent.

What you get

  • Dual-audience interface audit for existing marketplaces
  • Listing card system — variants for different inventory types and states
  • Search and filter architecture — primary and secondary filter layers
  • Trust signal design system — badges, ratings, verification indicators
  • Full marketplace UI design — all pages, all states, all breakpoints
  • Mobile-specific layouts for all critical flows
  • Developer handoff — complete specifications and assets
A marketplace interface that works for one side at the expense of the other is not a design success. Liquidity requires both sides to find value — and the interface is where that value is either made legible or lost.

Frequently asked questions

How do you approach the listing card design for a marketplace with varied inventory?

The listing card is the atomic unit of a marketplace — it appears on the homepage, in search results, in category pages, and in saved searches. It has to communicate the most commercially relevant information about a listing in a constrained space, work for inventory that varies enormously in price, condition, and specification, and convert at a reasonable rate from impression to click. We design card systems with variants and fallbacks that handle inventory diversity without breaking the visual consistency.

How much filtering is too much filtering?

More than most marketplaces apply. The instinct is to add filters for every attribute — because every attribute is relevant to someone. The result is a filter panel that overwhelms the buyer and produces filter combinations that return zero results. The right approach is to expose the filters that eliminate the most irrelevant results for the most buyers, group the rest under an 'advanced filters' pattern, and design the zero-results state to help buyers recover rather than abandon.

How do you design trust signals for a marketplace where the seller identity matters?

In marketplaces where the seller is a significant part of the trust decision — vintage goods, high-value items, specialist services — the seller identity needs its own design system. Verified seller badges, response time indicators, review counts and scores, years on platform — each of these signals needs a visual treatment that communicates its meaning at a glance. We design trust signal systems that scale from a new seller with no history to a verified power seller with hundreds of transactions.

How do you handle mobile design for a marketplace?

Marketplace mobile design is its own discipline. Buyers increasingly browse and transact on mobile — which means the listing card, the search and filter experience, and the enquiry or purchase flow all have to work on a small screen. But the information density requirements of a marketplace — multiple images, specifications, pricing, seller details — create real constraints on mobile. We design mobile-first where the data supports it, and always with a distinct mobile layout rather than a compressed desktop one.

Can you design for a marketplace that operates in multiple languages?

Yes. Internationalisation is a design constraint that needs to be built into the system from the start — particularly for listing cards and search interfaces where text length varies significantly across languages. We design component systems that accommodate string length variance without breaking the layout.

Design the interface that serves both sides.

Tell us about your marketplace — the vertical, the supply and demand dynamics, and where the interface is creating friction. We'll tell you what the right engagement looks like.