If You can't pay for different databases per company, the division into schemas is enough to get started with. Schemes can even do the job in modular monoliths. On the subject of the data layer with microservices, you need to make the most of the possibilities they provide – namely, https://securitysystemintegration12334.win-blog.com/17847469/a-simple-key-for-modular-software-suite-unveiled