No one appreciates when the previous owners of a house leave behind something unwanted. Of course, there are some things that are easier to get rid of than others. If it is a smell or an odor that was left behind, this could be very difficult to remove. Tobacco odor is one of the most difficult odors to get rid of. This is because tobacco smoke particles are so small that they can pass through most filters and the smoke can leave a film on many surfaces that retain the smell. If a light-bulb is left behind, the smell could resurface every time the light is lit and the bulb heats up. Unfortunately, a lot of work will be required to get rid of the odor. Appliances, insides of cabinets, walls and ceilings might all need to be cleaned off sometimes more than once.
There are some devices that are supposed to be able to remove the odor through the use of ozone, but the effectiveness of these devices is sometimes disputed, and they do have some major safety concerns.