Wall & Fifth

Marketplace conversion optimisation. Two-sided trust gaps, systematically fixed.

Conversion in a marketplace is not one funnel — it is two overlapping funnels with a transaction in the middle. The seller funnel converts a potential seller into an active listing. The buyer funnel converts a visitor into an enquiry or a transaction. Where they meet — the moment a buyer decides to contact a seller — is the most fragile point in the entire system. Wall & Fifth finds where both funnels are leaking and fixes them.

£3k / month

Starting retainer

3–4 maximum

Clients at any time

12+ internally

Ventures built

No lock-in

Commitment

Two funnels, one platform

Every marketplace has two conversion funnels running simultaneously, and they are interdependent in ways that make optimising one without the other ineffective.

The seller funnel: potential seller discovers the platform → evaluates whether it's worth their time → creates a listing → maintains the listing → becomes an active, high-quality supply contributor. Each step in this funnel has its own conversion rate, its own friction points, and its own set of interventions that improve it.

The buyer funnel: visitor arrives → discovers relevant supply → evaluates a listing → contacts the seller or transacts → returns for future purchases. Again, each step has its own conversion rate and its own failure modes.

The two funnels interact: poor seller conversion produces thin supply, which produces poor buyer discovery, which produces low buyer conversion, which reduces seller motivation to maintain listings, which further reduces supply quality. A marketplace in this spiral cannot be fixed by optimising one funnel in isolation.

Seller acquisition conversion

Seller acquisition fails at three main points. First, the seller value proposition page — often called "sell with us" or "list your item" — doesn't make a compelling case for why this platform is worth the seller's time compared to the alternatives. It leads with platform features rather than seller outcomes.

Second, the listing creation flow is too complex. Sellers abandon listings when the creation process requires too many fields, too many steps, or forces decisions they're not ready to make. Every field that isn't essential to the buyer's search is a potential abandonment point.

Third, time-to-first-signal is too long. A seller who creates a listing and receives no engagement for two weeks has no reason to believe the platform is working. Building in earlier feedback — listing views, saves, or a "your listing is live and being seen" notification — maintains seller motivation through the early period before first contact.

Buyer-to-transaction conversion

Buyer conversion fails most predictably at the listing page — the moment of highest intent and highest friction. The buyer has done the work of finding a relevant listing. The conversion barrier at that point is purely trust: trust in the seller, trust in the listing accuracy, trust in what happens after contact is made.

The search-to-listing conversion — the click-through rate from search results and category pages to listing pages — is also significant. Listing cards that don't surface the right signals produce low click-through regardless of the quality of the underlying supply. We address both: the card design that earns the click, and the listing page design that converts the click into contact.

The trust gap — where most transactions die

The trust gap is the moment between a buyer's decision to enquire and their actual act of enquiring. In that gap, doubt accumulates. Is this listing real? Is the price correct? What happens if I enquire and the item is no longer available? What are the payment terms? Will the seller respond?

Each of those doubts is addressable through design. Real listings are signalled through recency indicators and seller response rates. Price accuracy is supported through "price reduced" or "verified price" signals. Post-enquiry clarity comes from a clear description of the process. Response rates are displayed on seller profiles.

None of these interventions is novel. What is novel is building them into the architecture systematically rather than applying them as patches. A trust architecture designed from the start produces better conversion than the same signals bolted on after the fact.

How we work

Two-funnel audit

We map both funnels — seller acquisition and buyer-to-transaction — and identify the conversion rate at each step. We use analytics data where available and expert review throughout. We produce a prioritised list of interventions ordered by impact and effort.

Trust architecture review

We specifically audit the trust signals at each stage of the buyer journey — from the homepage through to the listing page — against the trust architecture framework. We identify which signals are missing, which are present but not prominent enough, and which are creating friction rather than reducing it.

Implementation

We implement the changes — design, copy, structure. For marketplaces on an embedded partner retainer, conversion optimisation is an ongoing programme: instrument, test, measure, iterate.

What you get

  • Two-funnel conversion audit — seller acquisition and buyer-to-transaction
  • Trust architecture review — signals mapped across the full buyer journey
  • Seller value proposition improvements
  • Listing creation flow simplification
  • Listing page trust signal improvements
  • Enquiry flow friction reduction
  • Analytics instrumentation — all funnel steps tracked
  • Ongoing conversion optimisation on retainer
A marketplace conversion problem is almost always a trust problem. The buyer found what they were looking for. The only thing stopping the transaction is insufficient confidence that it's safe to proceed.

Frequently asked questions

What's the single highest-impact conversion improvement for most marketplaces?

Usually the listing page — specifically the trust signals and the enquiry or purchase CTA. The listing page is where a buyer who has already done the work of finding a relevant listing makes the decision to commit or not. At that point, the buyer has high intent and the conversion barrier is purely trust. Improving the trust architecture of the listing page — seller credibility signals, transaction safety reassurance, clear next steps — typically produces the largest conversion lift of any single change.

How do you improve seller acquisition conversion?

Seller acquisition fails at predictable points: the value proposition page doesn't make the case for why this platform is worth the seller's time, the listing creation flow is too complex and produces abandonment, and the time-to-first-enquiry is too long to sustain seller motivation. We address each of those points — sharpening the seller value proposition, simplifying the listing flow, and designing mechanisms that give sellers early signals that the platform is working for them.

How do you measure conversion in a marketplace context?

Marketplace conversion has multiple layers: visitor-to-registration, registration-to-active-listing (seller), visitor-to-enquiry (buyer), enquiry-to-transaction, and transaction-to-repeat. Each layer has its own conversion rate and its own set of friction points. We instrument all of them and track them separately — because improving one layer while ignoring another can produce misleading improvements at the aggregate level.

What's the most common reason buyer-to-enquiry conversion is low?

Insufficient trust at the listing page level. The buyer has found a potentially relevant listing, but they can't establish enough confidence in the seller, the listing accuracy, or the transaction safety to take the step of making contact. This is often compounded by a high-friction enquiry mechanism — a form with too many fields, a requirement to register before enquiring, or an unclear description of what happens after contact is made.

Can you improve conversion without access to analytics data?

Yes. Expert review identifies the majority of conversion problems before they're confirmed by data. Analytics data accelerates prioritisation and allows us to quantify the impact of changes — but the underlying problems are usually visible to an experienced eye without it. We work with whatever data is available and identify what tracking should be added as part of the engagement.

Fix the leaks in both funnels.

Tell us about your marketplace and where conversion is falling short — seller acquisition, buyer-to-enquiry, or transaction completion. We'll tell you what's fixable and how.