the whole wifi mesh system is a good choice. https://www.tp-link.com/home-networking/deco/

sounds like it is the battery powered cam issue cause other devices work still going strong, like doorbell. You can post the model of the battery powered cam and then the TP-Link can do further...

I have a Deco P7 and M9 plus, they work perfectly and give me expected internet service; It works well with my local security cameras also. I think it can satisfy your needs. One more thing, P7 does...

I think this device might be faulty, you can contact their tech support to check the warranty.

You can contact the tech support of microsoft to get some help.

I agree with you. 3rd party VPN software is a good alternative.