iDerive Analytics Platform

Category and brand maturity drive the split more than any universal rule. For a mature brand in a branded-search-dominated category (established supplements, legacy CPG), a reasonable starting split is 65% Sponsored Products / 15% Sponsored Brands / 10% Sponsored Display / 10% DSP. Brands in commodity categories without a dominant search term benefit from pushing Sponsored Brands higher (25%) and DSP harder (20%) to earn share of voice rather than defend it. The common mistake: brands running $50K/month on Sponsored Products with zero DSP because Sponsored Products feels more measurable, leaving 30–40% of addressable demand unreached.

Holdout-market testing is the only clean answer. Pause Amazon ad spend in a geographically controlled holdout market for 3–4 weeks while running normally elsewhere, and measure DTC lift in the control versus holdout. AMC's cross-channel overlap reports help but require DSP plus a non-trivial identity stitch between Amazon shoppers and DTC CRM. Anything short of holdout testing is correlation, not causation, and correlation gets you a 70% overattributed halo number that justifies any budget decision you want. Most brands we work with discover actual halo is 15–25% of what their previous agency was claiming.

Amazon agencies typically charge $3K–$15K/month for management retainers and $8K–$20K/month for full-service engagements that bundle ads, creative, catalog ops, and case management. Some agencies pair the retainer with a percentage of ad spend (2–5%) or a percentage of marketplace revenue (3–8%). Performance-only deals that charge 15–25% of ad spend with no retainer exist but are rare. Most agencies don’t take that risk below $500K annual Amazon revenue.

You own your Amazon ads account, not the agency. A reputable agency operates with user permissions inside YOUR Seller Central or Vendor Central login, never a parallel account under their banner. If an agency insists on running ads through their own account, walk away. When the contract ends with an agency that owns the account, so does your PPC history, keyword learning, and account-level eligibility. Nectar never runs client ads out of its own account.

Hire an Amazon agency above $250K/month in revenue, consider it between $50K and $250K/month if you don’t already have a dedicated internal marketer, and stay DIY below $50K/month where the learning curve is cheap and the upside of expertise is modest. Between $50K and $250K/month, PPC optimization becomes a second job. Most solo founders break here. Above $250K/month, the opportunity cost of your time plus the compounding damage of a poorly run account usually makes hiring an agency a cheaper decision than staying in-house.

Four non-negotiables: (1) all ad accounts operate under your login credentials, not the agency's; (2) all raw data — AMC queries, campaign builds, search-term reports — is yours, exportable on 30-day notice in usable formats; (3) creative IP (photography, video, A+ Content) transfers to you on payment with clear commercial usage rights; (4) a no-solicit or neutral-zone clause that prevents the agency from pitching direct competitors during the engagement using your performance data. Agencies that push back on any of these are optimizing for their leverage, not yours.

Run a structured diagnostic on the three levers an agency actually controls: ad efficiency (campaign structure, negative keyword hygiene, bid discipline), catalog optimization (listing quality, A+ Content depth, keyword coverage in titles and bullets), and reporting cadence (what gets proactively flagged versus what's reactive). Pull 90 days of Sponsored Ads reports and score against category benchmarks. A good agency shows continuous experimentation signal in the data; a coasting one shows flat campaign structures untouched for months. You don't need an RFP to know whether your agency is coasting. You need two hours with your data and a category benchmark.