Startup Idea : Happy people/preserve the environment

Every day, all people throw away stuff. Most of them are vital for some people. Or some people will pay to take them. In the other hand each thing that we throw away is an evil for our environment. We can do better for our country, we can help each other, we can help our air, we should think for our children. By this app a people can inform the other about his stuff: location, kind of stuff, condition and a phone number or other contact. If someone is thinking that has something value, he/she can put a price (minimun price).