I want to point out that buying a new car is different from buying a used car. With a new car (unless it's something exotic), there are PLENTY of other cars out there. If you miss out on a good deal, another will come along. And it seems like most of the advice is more applicable to purchasing a new car.
With a used car, if you're looking for something specific in terms of make, model, trim, miles, and condition, the supply just may not be there and you have less leverage. Your "number" has to be realistic and you need to weigh the desire to "score a deal" against getting that particular car. If you miss a deal on a four year old Tiguan with 23k miles over a few hundred dollars, are you going to find another one? Or are you going to end up having to choose from Tiguans with the expected 40-60k miles on them? If you don't care whether it's a Tiguan, a RAV-4, a CR-V, Santa Fe, Sportage or whatever, you've got a lot more flexibility.
Something like mileage is more or less important to different people. To some (like me), low mileage is worth a LOT more than price guides give credit for.
With a used car, if you're looking for something specific in terms of make, model, trim, miles, and condition, the supply just may not be there and you have less leverage. Your "number" has to be realistic and you need to weigh the desire to "score a deal" against getting that particular car. If you miss a deal on a four year old Tiguan with 23k miles over a few hundred dollars, are you going to find another one? Or are you going to end up having to choose from Tiguans with the expected 40-60k miles on them? If you don't care whether it's a Tiguan, a RAV-4, a CR-V, Santa Fe, Sportage or whatever, you've got a lot more flexibility.
Something like mileage is more or less important to different people. To some (like me), low mileage is worth a LOT more than price guides give credit for.