https://mechgroupbuys.com/that website will help you with groupbuys, a group buy is a process through which we, as a community, can use our collective buying power to purchase goods at a reduced price or at all. Some Group Buys take advantage of price breaks to offer products to the community at a more desirable price, often at the cost of the GB organizer's time/efforts. Others simply give us the ability to make something happen that otherwise would have too much cost/risk associated with it for a vendor to buy into it and bring it to market themselves.
Most of the time groupbuy items wont ever get run again so it is kind of a one time thing.