Since the possibility of disputes is always present your agreement must include a place to cover how any disputes will be handled. This way everyone has already agreed to how these disputes are to be taken care of and cannot argue the point and cause further problems for the rest of the members of the venture. This may end up being the most important area of your agreement and should be filled out very carefully to avoid any possibility of a legal challenge.
Profit Division_ The financial aspect of a business is often the root of all issues. Before going into the commitment, clearly define the profit sharing process and percentage of all parties. This may be based on what each partner will bring into the table_ skills, finance, or other wise.