A reseller made $9,400 in sales last year. At tax time, she handed her accountant a pile of PayPal screenshots and a shoebox of receipts. She owed $2,100 in taxes she hadn't planned for — and missed $1,800 in deductions she could have claimed. Don't be her.

Why Most Resellers Hemorrhage Money at Tax Time

Most part-time resellers run their business on gut feel. Buy cheap, sell higher, pocket the difference. Repeat. It feels profitable when the money hits your PayPal account, so you assume you're making money. But gut feel isn't accounting. Accounting is numbers. And at the end of the year, when you sit down to file taxes, the difference between feeling profitable and actually being profitable becomes very real.

Here's what almost every small reseller misses. You see a listing sell for $85. The money hits your account. You feel like you made $85. But you didn't. eBay took 13% of the sale price as fees. PayPal took another 3% of what was left. You paid for a shipping label. You maybe spent $20 on gas to get to the garage sale where you bought the item in the first place. By the time you add up all the actual costs, that $85 sale might have netted you $45. You won't know that unless you track it. And most resellers don't.

They also don't track tool subscriptions. If you're paying for Find It – List It, for Sellfy, for scheduling software, or for accounting tools, those are 100% tax deductible business expenses. But they only matter for your taxes if you actually log them. A year-long subscription to a reselling tool might cost you $120, but it could save you $400 in taxes by lowering your taxable income. You only capture that savings if you track it.

By December, most part-time resellers have no idea what their real profit actually was. They sold a lot of stuff. Money came in. Some money went out. That's not a financial picture. That's a mess. And when it's time to file taxes, the accountant is guessing as much as you are.

The Three Numbers You Must Track for Every Single Sale

Tracking your resale income doesn't require fancy software or an accounting degree. It requires discipline and four numbers. Just four. If you track these four numbers for every single sale you make, you're ahead of 90% of part-time resellers in America.

The first number is what you paid. This is your cost basis. If you bought something at a garage sale for $8, that's your cost. If you bought it on eBay, your cost includes the shipping you paid plus the item price. Your cost basis is the total amount of money out of your pocket to acquire the inventory. This is the most important number because it directly affects your profit margin calculation.

The second number is what you sold it for. This is your gross sale price. If you sold something for $35 on eBay, your gross sale price is $35. Not what you'll receive after fees. The full price the buyer paid. You need both numbers to calculate your true profit.

The third number is your costs. These are the platform fees, the shipping fees you paid to send the item, and any packaging materials. If eBay took $4.55 in fees and you paid $6.50 for a shipping label, your costs are $11.05. Some resellers also include a small percentage for packaging materials like boxes and tape. That's optional, but tracking it gives you a more accurate picture.

Those three numbers give you the fourth number: net profit. Net profit equals your sale price minus your cost basis minus your platform and shipping fees. That's your actual profit. If you sold something for $35, it cost you $8 to buy, and your fees and shipping were $11.05, your net profit was $15.95. Write that down. Do it for every sale.

The Simple Spreadsheet That Takes 2 Minutes Per Sale

You don't need QuickBooks or Wave or any fancy accounting software to start. You need a spreadsheet. Open Google Sheets or Excel and create five columns: Date, Item, What I Paid, Sold For, and Platform Fees plus Shipping. Update it the day the item sells. Don't wait until the end of the month to batch everything together. You will forget costs. You will get confused about which item is which. Update it immediately while the transaction is fresh in your mind.

Add a sixth column called Net Profit and use a simple formula. In Google Sheets, it's: =D2-C2-E2 (sold for minus what you paid minus fees). Copy that formula down and it calculates automatically for every row. Now you have a live view of your profit on every single sale.

Add one more optional column: Category. Use this to tag what type of item sold. Clothing, electronics, furniture, collectibles, whatever categories you tend to source from. At the end of the month or quarter, you can see which categories are most profitable. You might discover that you make better margins on electronics than clothing. Or that furniture takes too much space for the profit it generates. This data guides your sourcing decisions going forward.

At the end of the year, sum up your columns. Total revenue is the sum of what you sold everything for. Total costs is the sum of what you paid for all items. Total fees is the sum of all your platform and shipping costs. Total net profit is the sum of your net profit column. You can also calculate your overall profit margin by dividing total net profit by total revenue. If you sold $5,000 worth of items and made $1,250 profit, your profit margin is 25%. That's the number that matters.

What You Can Write Off as a Reseller

Once you have your sales tracked, the tax deductions become obvious. Your sourcing costs — the actual price you paid for inventory — is your cost of goods sold, or COGS. That reduces your taxable income dollar-for-dollar. If you bought $3,000 worth of items and sold them for $6,000, your gross income before other deductions is $3,000, not $6,000.

Every mile driven to a garage sale, thrift store, estate sale, or post office is deductible. In 2024, the IRS mileage rate was $0.67 per mile. If you drive 100 miles a month sourcing and shipping, that's $67 a month in deductions, or $800 a year. Keep a simple log or use an app. The deduction is real.

Your platform fees are deductible. Every 13% eBay takes, every 3% PayPal takes, every Poshmark fee — that's a business expense that lowers your taxable profit. These are already tracked in your spreadsheet, so this is simple.

Your app subscription is 100% deductible. If you're using Find It – List It to run your resale business, that's a tool expense. Same with any scheduling software, photo editing software, or accounting tools you use specifically for reselling. Track the annual cost and deduct it.

If you store or photograph inventory in a home office, a portion of your home rent, mortgage interest, utilities, and insurance may qualify as a business deduction. The IRS allows either a simplified method (a flat $5 per square foot of dedicated office space) or detailed tracking. With a 100-square-foot storage area, you could deduct $500 a year just for the space. Consult a tax professional on this one, but it exists.

Packaging supplies are deductible. Every box, roll of tape, bubble wrap, poly mailer, and shipping label comes out of your taxable income as a business expense. If you spend $200 a month on packaging, that's $2,400 a year in deductions.

How Find It – List It Tracks This For You

The Expert and Power plan users get built-in bookkeeping tracking. Every time you scan an item with Find It – List It, the app logs the item name, your buy price, the suggested list price, and an estimated profit based on historical sold data and fees. At the end of the month or quarter, you have a complete record of every item you evaluated, what you paid, and what you're estimated to make.

You can export that data directly from the app and hand it to your accountant at year-end. No spreadsheet juggling. No guessing about dates or amounts. No shoebox receipts to organize. The data is already there. You copy it over, hand it off, done.

This saves you hours of work at tax time. It also saves your accountant hours of work, which translates to lower accounting fees. And it puts you in a position to claim every deduction you're entitled to, which can be worth thousands of dollars if you've had a good year.

Start Today, Not Next Month

The difference between a hobby and a business is records. Hobbies are casual. Businesses are tracked. Start tracking every sale this week. Not next month. Not after the holidays. This week. Create that spreadsheet. Update it for every sale from this moment forward. In three months, you'll look back and have a crystal-clear picture of what you actually made.

Your future self at tax time will thank you. Your accountant will thank you. And if you decide to scale reselling into a full-time income, you'll already have months of historical data to show banks if you ever want to take a loan or get a business line of credit. Tracking isn't just about taxes. It's about building a real business, not a side hustle.