I hiaghly recommend Neventum services, I have worked with them a couple of times and they have the capacity to adapt their proposals to the needs you have for each event.
Totems Communication and Architecture is a dutch-german design company and our main work is within the fields of (temporary) architecture, interior communication, product design, content research, nation branding and project management. Our locations in Amsterdam, Düsseldorf, Stuttgart und Shanghai enable us to deliver great design all over the world. With over 15 Years of expierence we can design exactly what you want!If you want to, our service can include everything, from scratch till trash. We are mainly working at international exhibits and fairs.