The increasing number of COVID-19 cases has placed pressure on medical facilities. Against this backdrop, the Tokyo Metropolitan Government established a facility for mild and asymptomatic COVID-19 cases by using existing hotels. These kinds of facilities were established in several countries, and represented a spectrum from hotel-like to hospital-like care. In this article, we focused on implementation and related strategies for establishing such a facility in Tokyo as implementation research, while ensuring patient and staff safety. This facility had three functions: care, isolation, and buffering. For the implementation strategy, we used several strategies from the Expert Recommendations for Implementing Change (ERIC) to implement functions similar to an ordinary hospital, but using fewer inputs. This experience can be applied to other resource-limited settings such as that in less developed countries.