With a focus on providing a complete, long-term IoT solution, there were successfully installed in the building 21 Vicki LoRaWAN® Smart Radiator Thermostats together with 21 Vicki Anti-vandal protective cases, 4 MClimate Humidity & Temperature Sensor LoRaWAN® coupled with 1 MClimate CO2 Sensor delivering remote access to monitor and control temperatures in all the office and common spaces. The installation process required no major, time-consuming, or costly renovations. These innovative devices gather a wide range of data on user consumption habits, providing detailed recommendations for heating and air quality optimization giving the management the flexibility to set tailored schedules for individual rooms as well as fro the entire premises. The implementation of the MClimate complete solution for optimal temperature, humidity and CO2 reduction, resulted in the impressive 31.25% savings from heating costs and improved the working environment of the whole staff. What’s more, the return on the investment (ROI) was more than exceptional, with a short payback period of 14 months. Dedicated to improving the CO2 footprint of old buildings in the long run, MClimate devices have 10 years battery life which is the longest-lasting battery on the market. By embracing these smart solutions Cosmos IoT managed to effectively upgrade energy efficiency, reduce costs, and introduce sustainable practices.