Asking for advice for stealthy audio recording gear for a home. This is a completely legal use-case (according to relevant state laws where it will be installed) and will help a vulnerable person facing threats. Looking for audio only, and must be capable of stealthy install.

It has been tricky to find surveillance equipment for audio recording (due to the many legal complications?) and impossible to find them with reliable reviews. Anyone with direct experience with the equipment? Concerned about audio isolation, effective distance, and overall quality. The few solutions I've tried so far have abysmal audio quality, requiring extensive editing in audacity to be somewhat usable.

2.4 or 5 ghz wireless is ideal for communication and want something that can be plugged in (not require frequent battery changes) capable of streaming directly to cloud storage but I haven't found a single device that meets these criteria.

The best I've found so far are microphones with RCA connectors designed to add audio to a video stream that is heading to a local DVR/NVR. I could possibly combine one of these RCA-connected microphones with a wifi device that has rca in (designed for wireless bridging to a DVR) but this is not ideal.

Any help / pointers / tips greatly appreciated