- 01
New-customer CAC, not blended ROAS
Ask how the agency separates new from returning customers in its reporting. A blended return can hide expensive first orders, so the proposal should show new-customer acquisition cost by channel and category.
- 02
Margin and returns in the LTV figure
In retail, lifetime value means little until product margin, discounts, fulfilment and returns are taken out. Ask whether LTV is reported on contribution margin after returns and at what level, such as SKU or category.
- 03
A retention team, not just an acquisition team
Raising LTV depends on email, SMS, loyalty and post-purchase journeys as much as on media. Check whether the agency has retention specialists who audit existing flows and consent capture, or only buys traffic.
- 04
Measurement that reconciles platforms with sales
GA4, ad platforms and your order or CRM data will disagree. Prefer agencies that set up server-side tracking or offline conversion feeds and explain how they will reconcile the numbers before scaling spend.
- 05
Independent retail evidence
Look for retail or ecommerce results judged by a third party, such as the UK Paid Media Awards or UK Search Awards winners lists, rather than relying on case studies the agency publishes about itself.
- 06
Trade-calendar and store awareness
Many retailers trade across city-centre stores, retail parks and online at once. Ask how the agency plans spend around peak trading, stock availability and in-store sales, not only around the ecommerce site.
- 07
Compliance in retention and promotion
Email and SMS to existing customers rely on the PECR soft opt-in, and reviews and prices in ads fall under the CMA's DMCC Act guidance. Ask how the agency handles both before it builds retention or promotion campaigns.