Most people leave money on the table when buying a used car — not because they're bad negotiators, but because they show up without the right information. Negotiation isn't about being aggressive. It's about having data the seller doesn't think you have.
Look up the specific year, make, model, trim, and mileage on KBB (kbb.com) and Edmunds (edmunds.com). Get both the private party value and the dealer retail value. Search your local area for comparable listings. Know the market price before you say a single word to a seller — this is the most important prep step.
Every documented issue is a negotiating point. Run a history report. Grade the model year on Caropsy to understand what's known to go wrong on this specific car. Get quotes on any needed maintenance (tires, brakes, fluids). Arrive knowing the car's problems better than the seller does.
After your test drive, ask: "What's the best you can do on this?" Don't name a number yet. The seller often comes down more than you'd expect just from being asked. Whatever they say, pause and let the silence work. A three-second pause after a counter-offer is one of the most effective negotiation tools available.
If the car is listed at $18,000 and you've determined it's worth $16,500 in current market conditions, open at $15,500. You're not insulting anyone — you're creating room to meet in the middle. Present your reasoning: comparable sales, needed maintenance, any issues found during inspection.
The single most effective negotiating tool is genuine willingness to leave. "I appreciate your time. I'm going to think about it and let you know." Then actually leave. Prices drop more often after someone leaves than during any conversation. If the seller doesn't call back, the price wasn't going to move anyway.