Never answer "What's your monthly budget?" directly—dealerships use this to manipulate financing. Avoid revealing your trade-in value too early; they'll lowball you. Don't admit you're in love with a car or that you need it urgently. Never say you're not a good negotiator. Skip discussing your down payment, credit score, or how long you've been shopping. Keep your financing pre-approved and don't mention monthly payments until the final price is set. Focus on the out-the-door price to avoid hidden fees. Stay calm, informed, and in control.