Perhaps something built specially for this purpose only should be cheaper - multi purpose or odor type units. We recently moved into a new leased property and just realised that there will at times be sewage odor in the atmosphere at sundry times. We are not sure where this could be coming from nor can we tell how soon it could/shall be repaired (if already acknowledged as a repair case). We have the option of relocating to another property but the current one meet several of our needs (such as faily high wall-fencing for privacy, cement paving, etc) that we would rather find a workaround (if at all possible) than to forfeit it. It appears closing doors and windows help control this but we needed to clever way to know when the pertinent odor is in the atmosphere so we could act accordingly - as remaining shut is not that practical. So we thought an electronic detector for this odor type could be able to help out. It shall not be the best but I reckon it is ever godly virtuous to take whichever God's Providence appoints patiently as ultimate resolutions are sought or awaited.