TL;DR
Track cost, sale price, and fees on every flip in a simple system. Your real profit is what is left after cost, fees, and shipping, so log those, set aside money for taxes, and review monthly.
Reselling can feel profitable while quietly losing you money. An item sells for more than you paid, so it feels like a win - but once you count what you paid, the gas to pick it up, shipping, and fees, the real profit can be far smaller than it looked. I am Nicole, and tracking my numbers is what turned a fuzzy side hustle into a business I could actually make decisions about. You do not need anything fancy to start.
Record your real profit, not the sticker gap
The number that matters is what you actually keep, not the difference between what you paid and what it sold for. Real profit is the sale price minus your cost, minus any selling or shipping fees, minus other costs to get it sold. When you log a sale, capture all of those so your numbers reflect reality. Tracking only the sticker gap makes you feel richer than you are and throws off every decision.
Log costs and fees too
Your sale price is only half the picture. What you paid for each item, shipping supplies, mileage, and any platform or payment fees all eat into profit, and in many places genuine business costs matter for taxes too. Keep a simple running log of what it costs you to buy and sell, with receipts where you can. Even a basic record makes tax time easier and shows what your flips really net.
- Log cost, sale price, fees, and shipping for every flip
- Calculate real profit as sale price minus all costs and fees
- Set aside a portion of profit for taxes as each flip pays out
- Review your numbers monthly so nothing piles up
Keep it simple at first
You do not need accounting software on day one. A single spreadsheet with columns for item, date bought, cost, date sold, sale price, fees, and profit covers most resellers early on. What matters is consistency - updating it every time you buy or sell. As your volume grows you can move to dedicated apps, but a neglected fancy tool is worse than a simple list you actually keep current.
Use the numbers to make decisions
Tracking is not just defensive. Clear records show which categories make the most profit, which sourcing spots pay off, and whether your income is trending up or down. That insight is how you decide where to focus your sourcing, what to stop buying, and when you can afford to scale or go full-time. Numbers you actually look at turn reselling from guesswork into a business.
Start tracking from your very first flip. It is far easier to keep clean records from the beginning than to reconstruct a chaotic year at tax time. A simple, consistent system pays for itself many times over.
Common questions
What number should I record as profit on a flip?
Record real profit: the sale price minus what you paid, minus selling and shipping fees, minus other costs to get it sold. The gap between purchase and sale price alone overstates what you keep. Your real profit is what actually lands after every cost is counted.
How much should I set aside for taxes?
The right percentage depends on your country, income level, and situation, so this is general guidance rather than tax advice. The important habit is separating a portion of your profit into a dedicated account as flips pay out. Check with a qualified tax professional for your situation.
Do I need accounting software to track my numbers?
Not at first. A simple spreadsheet with item, cost, sale price, fees, and profit covers most resellers early on. Consistency matters more than sophistication. You can move to dedicated apps as your volume grows, but a list you actually keep current is enough.
What costs should I be tracking?
What you paid for each item, shipping supplies, mileage, and any platform or payment fees - all of it eats into profit. In many places genuine business costs also matter for taxes. Keep receipts and log them, and confirm what qualifies where you live with a professional.
How often should I update my records?
Ideally every time you buy or sell, and review the whole picture monthly. Updating as you go prevents a chaotic scramble at tax time. A simple system you keep current beats a sophisticated one you neglect and have to reconstruct later.
Why track numbers beyond taxes?
Clear records show which categories are most profitable, which sourcing spots pay off, and whether income is trending up or down. That insight guides where to focus, what to stop buying, and when you can scale. Tracking turns reselling into a real business.
Keep going
Know your numbers and run a real business
Get the other 13 in the starter stack, plus the full FB Marketplace Resellers Club community - $9/mo, cancel anytime.
Join the Club