Our trustworthy and knowledgeable techs will assess the property to identify which smoke/carbon/heat detectors need to be installed to pass the fire department’s certification. If the assessment reveals any valid detectors in use at the property those detectors will remain. Should any valid detectors in use just need batteries, we have that covered too. There’s no up charge for the detectors and you can expect to pay that of retail prices at your local building supply store.