In Europe, consumer protection and especially data protection are very important, which strongly protects entrepreneurs and consumers. The company therefore has no choice but to behave correctly. Data protection and discretion as well as IT systems that manage this automatically are intrinsic and important, but especially standard in IT companies. Rumors of data being passed on or even sold are actually rather unrealistic. The company would be sued immediately, would lose directly and the reputation in the industry would be directly gone. But, what you should look out for is that the companies are professional and assure you that you will be discreet and objective with the clients. In addition, you can ask for and discuss the T&Cs and privacy statements. Furthermore, we recommend that you inquire whether the server locations are in Germany or the USA, for example, since completely different laws apply in the USA, which also sometimes handle data a little more loosely. Amazon Web Services and similar services in particular should not be completely ignored.