Brand, size and colour on the item
A trolley in three sizes and two colours is six items, and entering them as one is why a shop cannot say what is left. Keeping brand, size and colour as part of the item means the invoice records exactly what was sold — which is what a warranty claim will be matched against a year later when the customer has no box and no memory of the model.
Warranty and the return a year later
Luggage warranties run for years and the claim arrives without paperwork. If the invoice recorded the brand, model and date, you find it by party or by item in seconds and deal with the manufacturer properly. Shops that cannot find the bill absorb the replacement, which on a trolley bag is a serious cost for something a search would have answered.
Two peaks in the year
School reopening and the travel season drive most of the turnover, and both are ordered for in advance. Movement over the same weeks last year is the basis, and low-stock alerts on the fast models cover the peak itself. Ordering by feel is how a shop ends up long on a colour nobody wanted.
The number to watch
Stock ageing by model. Bags date on styling rather than on function, and a model that has not moved in two seasons will not move in a third. The movement report separates seasonal slowness from dead stock, and clearing the second group at cost frees capital that is otherwise sitting on a top shelf indefinitely.
Display stock and sellable stock
A bag shop keeps pieces on display that are handled, scuffed and eventually unsellable at full price, and most shops never separate those from real stock. Treating a display piece as its own stock line, or writing down its value when it comes off display, is what stops the closing figure from quietly overstating what you can actually sell. It also tells you the real cost of displaying a range, which is worth knowing before you agree to stock a new brand.