By Resale Kit Studio · Updated October 1, 2026
Start with money collected
For an individual sale, begin with the item price and any shipping charge collected from the buyer. Include a relevant transaction credit when it actually happens. Sales tax that the marketplace collects and remits is not money you keep, so leave it out of your revenue total. Avoid using a bank deposit by itself as your sale price: a payout may combine several transactions and may already have fees deducted.
Subtract each cost once
Subtract the purchase cost of the item, actual marketplace and payment fees, postage, packaging, refunds and other item-specific costs. Check how the marketplace displays the transaction so you do not subtract a fee that is already excluded from an amount you entered. Use one consistent method across your records. The workbook uses gross item revenue and separate actual expense fields, which makes each part visible.
A fictional worked example
Imagine an item bought for $8 and sold for $35. The buyer pays $8 for shipping. Recorded fees total $6, postage costs $8 and the packaging costs $1. With no refunds or other costs, recorded item profit is $35 + $8 - $8 - $6 - $8 - $1 = $20. These amounts are examples, not a fee schedule, typical outcome or earnings forecast.
Keep estimates separate from completed sales
Before a sale, use an estimate to decide whether a purchase or listing price makes sense. Enter your own fee assumptions in the free profit calculator. Some marketplace fees use a base that includes buyer shipping and sales tax, and fee rules vary. After a completed sale, replace assumptions with actual transaction amounts in your tracker. That is how you find out whether the decision worked.
Know what the number leaves out
Recorded item profit is useful, but it is not a complete business profit or tax calculation. General overhead, mileage, income tax and your time still matter. Keep separate records where needed. Profit margin divides recorded profit by sale price plus shipping collected. Return on purchase cost divides profit by the item cost. If an item was free, that second percentage has a zero denominator and should be shown as unavailable rather than as an enormous return.
Official reference: eBay selling fees. Consult the current policy before acting.