All traders want to always buy Bitcoin at a price cheaper than the market price. Apart from buying and selling on the ordinary, centralized crypto asset exchange, there is another option, namely a peer-to-peer exchange. In this exchange, asset prices are not “regulated” by the exchange manager, but directly by the users. In principle, a peer-to-peer (P2P) exchange is a crypto asset exchange that is similar to an online shop, aka a marketplace. The role of the stock exchange manager is only to bring together the seller and buyer of assets directly on one platform. In other words, for example, if you want to sell Bitcoin, you have a trading booth on that platform. It is also possible to place ads on that platform by specifying the selling price of the asset. The advantage of an exchange like this is that the seller is free to determine the selling price as he wishes and the buyer can freely look for price variations on the exchange. Buyers can even get a much cheaper price than buying on a regular exchange.
The difference would not be noticed that much even you got it on a cheaper price.Those p2p exchanges also sets their buy and sell price according to their will, it's also the same on exchanges that are centralized.
If you ever wanted to buy bitcoin for lower price, then try buying it away from exchanges. You can buy it directly to someone. A friend, or anyone that is willing to sell it those bitcoins to you at a considerably lower price.