Reseller sourcing math
How much should you pay for resale inventory?
Set a maximum buy price before you source. Work backward from a realistic sale price, subtract the costs you expect to pay, and protect the profit you need.
Start with a realistic sale price
Compare recent sold items that match the same brand, model, size, condition, completeness, and selling channel. A high active asking price does not show what a buyer actually paid.
Use a conservative expected sale price rather than the best sale you can find. If you normally accept offers, subtract your expected discount before working out the maximum you can spend.
- •Record the dates and prices of the closest sold comparisons.
- •Check whether shipping was included in those sale prices.
- •Adjust for defects, missing pieces, different sizes, and slower demand.
Calculate your maximum all-in acquisition cost
Maximum all-in acquisition cost = expected sale proceeds − estimated marketplace and promotion fees − seller-paid shipping − packaging − cleaning or repair − return or risk allowance − target profit.
The all-in acquisition cost includes the sticker price plus buyer premium, sales tax where applicable, inbound shipping, and any travel cost you allocate to that item. Subtract those extra acquisition costs to get your maximum sticker price or auction bid.
- •Estimate fees using the current rules for the actual marketplace, category, account, and promotion settings.
- •If shipping is charged separately to the buyer, include that revenue and its related fees and postage consistently.
- •Choose a target dollar profit that reflects your listing time and storage needs. The formula is an estimate, not a guaranteed outcome.
Worked example: what can you pay for a $60 item?
Suppose close sold comparisons suggest a $60 listing price, but you expect to accept a 10% offer. Expected item revenue is $54. For this illustration only, allow 15% for selling fees ($8.10), 5% for optional promotion ($2.70), $8 for seller-paid shipping, $1 for packaging, $2 for cleaning, and $15 target profit.
$54 − $8.10 − $2.70 − $8 − $1 − $2 − $15 = $17.20 maximum all-in acquisition cost. If the purchase also carries $1.20 in tax and $2 in allocated travel, the maximum sticker price falls to $14. The fee percentages are examples, not a statement of any marketplace's current rates.
Use a buy-or-pass record while sourcing
Write down the item identity, evidence for the expected sale price, condition, maximum all-in acquisition cost, actual asking price, and any unknowns. If the seller's price is above your ceiling, pass or revise the assumptions with better evidence.
A cheap item can still tie up cash and shelf space. Consider sell-through, listing work, storage, fragile shipping, authenticity, returns, and whether you can realistically describe the item accurately.
- •Ask: Would this still meet my target if I take an offer or postage costs more than expected?
- •Ask: Can I photograph, store, find, and ship it without disproportionate effort?
- •Record why you passed so you can improve later decisions.
Review the result after the sale
Compare the actual sale price, fees, promotion, postage, supplies, and profit with your estimate. Update your sourcing ceiling for similar products. Keep tax treatment and business accounting separate from this simple pre-purchase estimate.
Inzoly helps sellers organize product and inventory records and prepare seller-reviewed listing content. eBay is supported; Poshmark and Grailed publishing workflows are in beta. Shopify remains coming soon, and Bonanza direct publishing still requires seller authorization and a verified live test.
Frequently asked questions
Is there one good percentage to pay for resale inventory?
No. Your maximum price depends on realistic sold prices, fees, shipping, item condition, preparation costs, sell-through risk, and the dollar profit you require.
Should I use the listed price or the sold price?
Use relevant recent sold comparisons to estimate what a buyer might pay. Asking prices can provide context but do not establish a completed sale.
How do I account for free shipping when sourcing?
Estimate the postage and packaging you will pay and subtract them from expected proceeds before choosing your maximum acquisition cost.
Does Inzoly's free profit calculator include selling fees?
The free calculator shows gross profit and margin from the inputs you provide. Account for marketplace fees, shipping, promotion, taxes, returns, and other expenses separately.
Related reseller resources
Turn the workflow into a system.
Inzoly brings product records, marketplace listings, inventory, photos, orders, analytics, and seller-reviewed AI into one reseller workspace.