During plasma surface decontamination of hospitals' accommodations and medical instruments, one should expect some changes to occur on the surfaces of different materials exposed to plasma. In this study we have investigated effects of cold atmospheric plasma on four common materials likely to be found in medical facilities, namely medical polyvinyl chloride, polystyrene, stainless steel, and borosilicate glass. Two plasma configurations are used, one directly using an atmospheric pressure plasma jet (APPJ) and the other indirectly using plasma activated mist through a gliding arc discharge producing plasma activated mist. After plasma treatment, surface properties of the considered materials are investigated using water drop analysis, attenuated total reflectance Fourier transform infrared spectroscopy, and atomic force microscopy. Plasma is found to reduce bacterial contamination and on the same time alters, in different proportions, surface materials' properties such as wettability, surface energy, and roughness, of the treated samples. We have found that although direct plasma using APPJ can act more rapidly than indirect plasma concerning bacterial elimination from different materials' surfaces, indirect application through plasma activated mist is able to achieve the same bacterial death rate on longer time periods. This can be advantageous due to mild and best penetrating behavior of plasma activated mist on sensitive medical installations.