I have a Amcrest IP8M-FCT2999EW-AI it is a 2 way talk camera. It works with BI as expected; however the speaker on the camera is not very loud. It has both audio in and audio out RCA jacks. I am assuming that I can add an after market microphone and an aftermarket speaker. Is there any reco on where to search for this merch? Any reco on a good value? Side note: I also bought a Jennov PTZ 2 way talk camera. The speaker is very loud and works well with BI. I have not figured out how to use PTZ with BI. The PTZ works well but right now I need to log directly into the camera to use PTZ.

For a microphone, you need to read the specifications for that model of camera. I tried guessing one a few years ago and never got it right.
Speakers shoud be easier as I think a line output should be pretty standard. Being able to return items would take the risk out of either purchase.
Jennov ptz - others are searching for a camera with two way audio ! For ptz you need to understand which protocol it is using first then see if BI5 can do it.