Limited liability companies are easy to maintain while remaining extremely flexible, so it's not surprising that it is a popular choice among businesses of all different shapes and sizes. Often, owners of an LLC are self employed or run smaller businesses, where the simplicity of pass through taxation and a lack of annual requirements makes a lot of sense. Since the profits and losses are reported directly on the owners personal tax returns, filing taxes is much easier.
A partnership is a business relationship entered into by a formal agreement between two or more persons or corporations carrying on a business in common. The capital for a partnership is provided by the partners who are liable for the total debts of the firms and who share the profits and losses of the business concern according to the terms of the partnership agreement.
A series LLC is a form of limited liability company that provides liability protection to multiple "series". Essentially, it's a master LLC with separate divisions, each protected and operating independently. As an entity, the series LLC is geared towards businesses where investors own multiple companies, with each series being protected from the debts and obligations of the other series. Currently, only several states support this option, including Delaware, Illinois, Iowa, Nevada, Oklahoma, Puerto Rico, Tennessee, Texas, and Utah.
On the other hand, if you are not responsible for its tax, then you should declare the equipment in Part III of the Business Property Statement (Equipment belonging to others). Where equipment is declared in Part III of the Business Property Statement, the Assessor will also send a Notice to File to the person reported as the equipment's actual owner.