Security Camera Systems

So my house is currently wired up with 4 Lorex IP cameras going to my PoE switch. Elsewhere in the network I have a Lorex LNR 300 DVR which is configured to record from those cameras. I use the Lorex "netHD Stratus" app on both my Android Phone and my wife's iPhone to view the cameras remotely...

I am looking for a reasonably priced, solid security cameras PoE with DVR and two way audio capabilities. Want Internet monitoring (phone/computer) with connect 4-3.54Mbps upload speed from the home. This monitor my mother and keep her safe at home. Really appreciate any assistance on this!