As a mobile room system, containers can be used for all purposes thus providing a quick solution for room and storage problems at a fair. Rental containers can be used as a sanitary, storage, refrigeration, office, residential, construction, special, maritime, material or snack bar container. Container systems can be expanded up to large-scale production plants. Thus container rental can provide comfortable and adequate solutions as a mobile room rental service. As storage for debris, waste or hazardous materials, rental containers can serve as a short-term solution for fair organizers. Room containers can be easily and individually designed and quickly assembled for different purposes thanks to the modular construction system. Used or brand new containers are available for leasing or rent. The single room cells can create comprehensive quick-assembly halls and consistently combinable space solutions. Thanks to detailed consultation and planning, the following assembly of the container system can be carried out most effectively.