Know the difference between a good forecast and real profit.

Gross spread is not realised profit

If you buy for £20 and expect to resell for £50, the £30 difference is only a gross spread. Actual profit depends on the costs you really incur.

A simple realised-profit formula

Realised profit = sale proceeds − purchase price − actual selling costs − postage you paid − packaging − cleaning/repair costs − other attributable costs.

Use only costs that actually belong to the transaction rather than inventing future costs in advance.

ROI measures return on the money invested

A common sourcing ROI calculation is profit divided by the money invested in acquiring/preparing the item, multiplied by 100. Keep the formula consistent when comparing deals.

Margin answers a different question

Profit margin expresses profit as a percentage of sale revenue. ROI and margin can both be useful, but they are not interchangeable.

Use forecasts to decide; use realised numbers to learn

Forecasts help with the buying decision. Real outcomes tell you whether the model, category or sourcing channel actually worked. Resell AutoBot keeps resale estimates and True Profit as separate concepts.

Try the free resale profit & ROI calculator.