Inventory Planning for Accessory Sellers

Small range, full discipline

A seller with five SKUs needs the same inventory discipline as one with five hundred, at a friendlier scale. The discipline is three numbers per SKU: how fast it sells, how long a reorder takes, and how much stock you want on the shelf when the next order lands. Everything else in inventory planning is bookkeeping around those numbers.

Sell-through, recorded weekly

Count units sold per SKU per week, and keep the history. Weekly data shows the shape that monthly averages hide: the promotion spike, the seasonal rise, the slow decay of a model heading for retirement. For a small range the count is minutes of work, and it is the input to every other decision on this page.

Reorder point

The reorder point is the stock level at which the next order must be placed: expected weekly sales multiplied by the weeks a reorder takes, plus the safety stock you want on hand when it lands. The weeks figure comes from the quoted lead time plus transit, plus a margin for reality. Write the reorder point next to each SKU and look at it on the same day each week; inventory systems fail by drift, not by design.

Safety stock

Safety stock absorbs the two variables you do not control: demand spikes and schedule slips. Size it honestly. One extra week of demand is a margin; two is a policy; five is a cash habit. For accessories, safety stock in the consumable parts, such as mounts and cables, earns more than safety stock in slow models, because a missing accessory stops a sale just as effectively as a missing unit.

Seasonality

Where demand is seasonal, plan the peak as its own mini-budget: expected weeks of peak demand at the elevated rate, ordered to land before the window with a reserve for the promotions you actually run. After the peak, plan the run-down deliberately: what carries to next year at what storage cost, and what sells at a planned discount instead.

The aging report

Once a month, list stock by SKU and by age of receipt. Aging stock is information while it is still moving and a write-off once it is not. An SKU aging past two reorder cycles gets a decision: promotion, bundle, price move, or retire. Make the decision in writing with a date, because inventory decisions deferred are inventory decisions made by the warehouse.

Cash and shelf share the same limit

Inventory ties cash and space at once. Check both limits against the plan: the cash tied in stock at any date, and the shelf or bin space the plan requires. A plan that fits one limit and breaks the other is not a plan. Where the limits bind, the resolution is fewer SKUs, not thinner safety stock on the SKUs that sell.

The review

Close each quarter with a one-page review: sell-through per SKU, hits and misses against the reorder points, aging actions taken, and the changes for next quarter. The review is what turns inventory from a source of surprises into a system that improves.

The stockout post-mortem

Stockouts deserve the same review as returns, because they are returns of a kind: demand the business was not able to serve. After each one, write three lines, when the reorder point should have fired, why it did not, and what changes so the next one does. The causes are usually dull and fixable: a count that drifted, a lead time that grew, a spike that safety stock should have sized for. Post-mortems kept in the same file as the planning sheet turn stockouts from recurring embarrassments into the planning system's error log, and error logs are how systems improve.

The SKU retirement decision

Every range accumulates models whose turn has passed, and the retirement decision is where planning meets discipline. The evidence for retirement is arithmetic: sell-through below range average for two review periods, support cost above contribution, and no customer request in the log that another model fails to serve. Retire in writing with a date, sell through at a planned depth, and honor spare parts for the installed base for as long as the supplier will supply them. The habit matters more than any single decision: a range that knows how to retire stays small enough to plan, and a range that cannot retire becomes a warehouse with a website attached.

Demand signals worth recording

Beyond the sales count, three signals sharpen the plan: the question log, the returns reasons and the season's weather pattern. Questions forecast demand before sales confirm it, because customers ask about what they are about to buy. Returns reasons forecast the support load and the listing edits. And the weather overlay explains the demand blips that a calendar cannot, which keeps the safety stock sized to the real shape of the market. All three live in the same weekly review as the sell-through count, and together they turn the reorder point from a formula into a forecast.

Cash rhythm

Inventory planning is cash planning wearing a warehouse coat. Map the order cycle against the cash cycle: deposits leave before goods move, balances leave before goods land, and sales bring cash back over the weeks after. The gap between money out and money in is the number a growing seller actually manages, and it is visible only when the order dates and the sell-through share one sheet. Where the gap tightens, the levers are the assortment's, not the accountant's: fewer variants, smaller safety stock on slow models, and a reorder cadence that follows the data instead of the calendar.

The count that keeps the sheet honest

Weekly sales counts drift from reality through returns, damages and shrinkage, and the drift compounds quietly until the reorder points fire at the wrong times. Close the loop with a cycle count: a few SKUs counted every week on rotation, the whole range counted every quarter, and every variance written down with its most likely cause. Variances are information twice over, once as inventory correction and once as an operations finding, because a SKU that shrinks in the same corner every quarter has told you where the process leaks. The sheet that is counted is a plan; the sheet that is assumed is a story.