Don't say you want the monthly payment to not exceed a certain number. A car salesman tries to maximize profits and will simply artificially reduce your payment by extending the life of the loan or by requiring more money up front as a down payment. Even though the monthly payment is the most important factor for many buyers, you should never discuss this with the dealer during negotiations. When asked, simply respond by saying probably.
If you continue to be harassed, tell them that you are interested in financing but that you first want to agree on the price of the car. To become an effective negotiator, you must first familiarize yourself with the three different prices of a car. In fact, more buyers cite dealership negotiations on car lots as the most feared part of the whole experience. Some car sellers offer good deals to customers who know they're excited about their cars, but it's best to take the excitement out of the car-buying experience altogether, no matter what effect it may have on the dealership.
Instead, the ultimate goal is to get the dealer to take such a low price that they are willing to pay for the car in exchange for the opportunity to get the metal out of the lot. For example, the dealer will provide you with a loan for a car through one of its financial partners at 5% interest and add an additional 2% profit margin. To determine your ability to pay, the seller will usually ask you what you do for a living and where you work. If you plan to change your current vehicle, don't tell the dealer until you've agreed on the price of the new car.
You wouldn't negotiate with a car salesman without the average car price; nor should you negotiate a car loan without information. Whether the salesperson shows you a Ferrari or a Chevy, their answer should always be to point out the car's problems and faults. Out the Door (OTD) is the dealer's language for the final total price of the car, including all taxes and fees. Saving enough money to buy a car with cash is certainly more difficult than getting a loan, so people assume that they should be rewarded for this achievement.
It's also natural for a car salesman to ask a buyer what they do for a living during the course of a conversation. Dealers love to quote cars in terms of monthly payment, leaving the purchase price out of the equation until documents are signed. Take it from someone who's been there, it's entirely possible to beat car dealerships at their own game.