Wallapop is a nice piece of software which gives you the ability to buy and sell items while dealing directly with the people involved in the transaction. Right off the bat, you'll have to create an account. The application comes with a friendly layout and the items available here are kept inside multiple categories. You can find stuff by going through different sections or by using the included search feature available at the upper part of the window.
Moreover, even if the price of a product is already listed, you can still negotiate with the seller and maybe you can get him to lower the price. Besides purchasing stuff with money, for sellers in your area you might also be able to offer them some other product in exchange. The majority of the items listed within the interface come with description and pictures.
Each user has its own profile on this platform and you can use it to check out reviews provided by other people that bought something from them. Another important feature is the incorporated chat system which simply lets you talk with users each time you want to buy something from them, or vice-versa. Sellers usually display their location and you can use this info to decide if a purchase is worthy or not.