hardwiring two cameras

I already have a hardwired dashcam in the front windshield, but I'm thinking about adding another hardwired dashcam to the back. Do I need to buy another separate add-a-circuit and DC-DC converter module? Supplies I used to hardwire first dashcam: Mobius Dashcam Add-A-Circuit DC-DC Converter...

I thought a new thread would be helpful to generate some more discussion on this topic. I've done a search but can't find much. I have fairly basic electronics knowledge so if you can contribute on this subject then it would also help others who may be asking the same question. The question is...