Effective haggling using mathematics

November 28, 2018

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Did you know that most of the people in the world pay less than the price given on the label when buying something? These buyers use a very well-known phenomenon called haggling to do this. Haggling can be described as a type of negotiation in which a buyer and seller debate about the price of a good, often leading into a better deal for the buyer. Although haggling is something that happens every day all over the world, a lot of people still have not mastered it. In this article, I will introduce you to the world of haggling and show you an example of a small mathematical model that will help you to get the best deals.

The basic idea of haggling

Let’s first get something clear: you cannot haggle everywhere you want. For example, in a Western European country you cannot haggle in a supermarket. Or can you? Choosing where you are willing to haggle or if you even want to haggle ever at all is the first decision you need to make. Some people think it’s not ethical to ever haggle at all, while others try to haggle as much as they can, wherever they go. For now, I will assume you are a person that is willing to haggle when possible. Then, what are some good things to keep in mind regarding haggling?
Firstly, you should know what a realistic price is for the item you want to buy and set that as a limit. Do not lowball (bid extremely low) sellers, since it will put them off really quickly which will only result in a worse deal. Try to bid at around 60% to 80% of the realistic price you have in mind. Secondly, you always need to get an idea of the seller. You can do this by for example having a short talk with the seller and asking them some questions. Do you feel like the seller is willing to lower his prices a lot, or do you feel like the seller is barely willing to fluctuate in his prices at all? Getting an idea of the seller will help you make better decisions when haggling. The last thing you should always keep in mind is to know when to walk away. Walking away can be seen as a last resort to really get to know whether a seller is willing to lower his prices or not. Walking away can be done in real life by literally walking out of the shop, but also on virtual marketplaces by saying that you will not buy the item. Keep in mind to only walk away when you have no other options left!

Using mathematics to haggle efficiently

One of the hardest things to decide as a haggling buyer is whether you start off with a bid instantly or ask the seller to first set his/her lowest price and then start bidding. By using mathematics, we can make this decision way easier. Let’s assume you are a person that haggles occasionally, and you want to buy a new pair of shoes on Marktplaats, a digital marketplace for second-hand items. You have found a nice pair of shoes and you message the seller. Should you ask the seller for his/her lowest price, or start the bidding straight away yourself? For this, we could formulate the following mathematical model:What we can conclude from this small model, is that asking the seller for his lowest price first will give you a better deal in the end, for every given p, b and c. Of course, this model has its flaws since we never know whether the seller and buyer really act the way given in the model (there are no psychological influences taken in account). What you can of course do is edit the model to the situation you are in and still find the best way of haggling.


Haggling is a phenomenon that occurs all over the world, so I can ensure you that you will stumble upon it at least once in your life. Before you start haggling, you need to make the ethical decision for yourself whether you approve or disapprove haggling. After making this decision, there are tips and tricks that you should keep in mind while haggling. If you really want to haggle the most effective way possible, you could formulate yourself a mathematical model in your situation. Solving this will give you the best possible haggling technique in the given situation. Combining your psychological and mathematical skills might actually make you the ‘haggling-master’ you have always wanted to be!
Fluentin3months.com: Haggling like your life depends on it
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Dit artikel is geschreven door Lars Beute

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