Bidding, Budgeting, and Placement Adjustment Decisions
The bid stack
Your effective bid is the base bid - set at keyword or target level, with a possible ad-group default - plus placement multipliers for top of search and product pages. Sponsored Products allows placement adjustments up to several hundred percent, and Sponsored Brands has a top-of-search multiplier. Sponsored Display placement control works differently and relies on bids and tactic choice.
Bidding strategies
Dynamic bids – down only lowers bids for clicks unlikely to convert. Dynamic bids – up and down raises them for likely converters and lowers the rest. Fixed bids keeps every bid at the set level. Down-only is the conservative default; up-and-down can raise costs sharply on high-intent queries.
Budgets
Budgets live at campaign level and can be grouped into portfolios with a shared cap. Daily budgets are averaged rather than hard ceilings - Amazon may overspend on a single day and pull back later - so judge pacing against the month and check the out-of-budget report before assuming bids are the problem. Scheduled budget rules can raise budget for known events.
Traps
Multiplying the placement adjustment into the budget, expecting a bid change to fix a campaign that runs out of budget by noon, and forgetting that a higher placement multiplier raises CPC and therefore ACOS. Another trap is treating one target ACOS as universal when your target must reflect product margin.
Rule of thumb
Set the base bid near your target cost per click (target ACOS × average order value × conversion rate), then add a top-of-search multiplier only for keywords already converting at or above that rate; raise budget before multiplier when impressions are capped.