The Sourcing Log: Record Every Buy

The columns

Every time you buy an item for resale, enter one row with these eight fields. A checklist format helps you enter everything that matters:

The columns are the same ones used in the inventory spreadsheet template, so your log and your full inventory sheet stay compatible.

• Date of purchase
• Source or marketplace where you bought it
• Buy price
• Extra costs (cleaning, transport, packaging)
• Landed cost (buy price plus extras)
• Resale estimate (what you think it will sell for)
• Target price (your minimum acceptable price)
• SKU or item code (a short code you attach to the item)

The landed cost column is the sum of what you paid plus any money you spent before the item was ready to list. For example, if you bought a jacket for 80 zł and spent 10 zł on dry cleaning, your landed cost is 90 zł. This is the number that matters for profit, not the purchase price alone.

The resale estimate is what you think the item will sell for when you list it. Be honest — this is the number you will compare against the actual sale later. If you are unsure, base it on similar listings you saw that recently left the market, not on wishful thinking.

The target price is your walk-away number. If you would not list below this price, write it down now so you do not accept a low offer later out of desperation.

Why the purchase date matters in Poland

In Poland, the tax treatment of a resale depends on two things: how long you held the item and whether you are selling as a private person or as a business.

If you sell a private item you owned for more than six months (the six months are counted from the end of the month of purchase), the profit is not taxed as income. For example, if you bought a coat in March and sold it in October, the holding period is more than six months and the gain is tax-free. If you sell the same coat in May, it has been held for less than six months and the profit must be declared in your PIT-36 return as income from the sale of private property — you can deduct the acquisition cost from the revenue.

This is why the purchase date column matters. Without it, you cannot prove how long you held an item if the tax office asks.

Buying items specifically to resell usually points to business activity, regardless of how long you held each item. If you are operating as a registered business, all sales are taxable on the same principles as other income. If you are operating as działalność nierejestrowana (unregistered activity), your quarterly revenue must not exceed 10,813.50 zł, and you must keep a simplified sales record and file a PIT-36 annually.

Platforms report sellers to the tax authorities under DAC7 when they have at least 30 sales or more than 2,000 EUR in payouts in a calendar year. Allegro counts all accounts of the same seller across Allegro and Allegro Lokalnie. The report includes only the number of sales and the amount paid out — it does not include your costs. Your sourcing log is the only record of what you spent, which matters if you operate as a business and deduct costs from your taxable income.

From log to profit

The free inventory spreadsheet template has formulas that turn your raw numbers into profit figures. You do not need to calculate manually — the spreadsheet works this out for each row:

• Net payout = sale price − marketplace fee − shipping you paid
• Profit = net payout − buy price − extra costs
• ROI = profit ÷ (buy price + extra costs)

These are the numbers that tell you whether a sourcing run was worth it. A positive profit means you covered your costs and made money. A negative profit means you lost money on that item. See profit by marketplace for how fees differ between Vinted, OLX and Allegro Lokalnie.

Weekly check: estimate versus result

Once a week, review the items you sold that week. For each one, compare what you thought it would sell for (your resale estimate) against what it actually sold for. This is not about judging yourself — it is about calibrating your estimates so future buys are more accurate.

If your estimates are consistently higher than actual sales, you are probably pricing too aggressively. If they are consistently lower, you are leaving money on the table. The weekly check catches this early, before you buy more of the wrong items.

Paper, sheet or app

The simplest version of a sourcing log is a notebook page, but a spreadsheet is easier to search and calculate with. The inventory spreadsheet template is free to download and already has the columns and formulas built in. Use whatever you will actually open after every buying trip — the tool matters less than the habit.

The sourcing log handles the moment of buying; the spreadsheet template handles the rest. See also the landed cost definition for more on how to calculate it, and the tax selling rules page for the detailed Polish rules on private sales.