First, determine whether your requirements are ISO900 1(QMS: Quality Management System) or ISO/TS 16949.
Secondly, you have determined the TUV logo required in the certificate (provided by all three companies you mentioned).
Then choose the certification bodies that provide services (Rhine, North Germany and South Germany).
1. Considering the service demand: Rhine, North Germany and South Germany can all provide ISO900 1, ISO/TS 16949.
Certification service. Do you only need a certificate or its service or value-added service for system authentication? It is suggested that the auditors provided by them can be evaluated from the aspects of professionalism and background, as well as the effectiveness of certification.
2. Consider the needs of your company's customers: If you are certified by ISO/TS 16949, do you want to ask your customers if they have designated any of the three certification bodies? If not specified, you will have more choices. For example, FAW-Volkswagen has designated Rheinland and SGS as suppliers for TS 16949 system certification.
3. Consider the certification price and related fees: the certification fees of the three institutions are different, and each company has its own quotation principle. Please contact them.
Overall evaluation: In China. Rheinland has the oldest qualification, the largest customer base and the most complete certification (products, systems, etc. ), higher fees, the largest number of auditors. North Germany and South Germany have their own advantages. Certificates are consistent in nature.