You can find tabletop versions that you just need to plug N play. This will likely work effectively first room, very much like a location heaters works well with only a small area. Main humidifiers, even so, connect to your heating system and air conditioning system and to your pipes. The price to install a humidifier to these sizeable components could be more pricey. If you need to know how humid is your house, check out this article about hygrometers.