It is a good backbone to understand the legal structures. Your choice of the legal structure has financial, fiscal and legal implications. The legal structure determines the liability! You should certainly first contact a consultant at the Chamber of Industry and Commerce [Industrie- und Handelskammer (IHK)]  or the Chamber of Skilled Crafts [Handwerkskammer (HWK)] and maybe discuss the matter with your/a tax advisor. Your choice in favour of or against a particular legal structure is never final. If your company's needs change, you can change its legal structure at any time. 

You are required to register your company in the Commercial Register [Handelsregister]. By registering in the Commercial Register, you assume all the rights and obligations of a merchant. Small businesses with simple and limited business structures as well as freelancers who are members of the liberal professions are not registered in the Commercial Register.

• it is rather easy and fast to realize
• a civil law partnership can be established both by tradesmen, joint practice, consortium and by freelancers,
• there are no special formalities that are necessary to this structure, except a written agreement
• there is no minimum capital requirement
• all of the partners are liable with their private belongings for all of the company's debts as well as mismanagement and force major
• you can agree on special rules in a social contract