Go Even Further

Faraday sleeves

Good

Mission Darkness

Avoid

The cheap, off-brand ones that look like glasses cases. They occasionally work but it's very easy to close them in a way that isn't 100% effective.

Camera blockers

Good

Buy the cheap ones that come in many sizes. You'll want to block all sorts of cameras from your laptop to the selfie camera on your phone to the large array on the back of it.

Avoid

NanoBloc. They're good quality and the designs can be fun but they don't have enough size variety and they're more expensive.

Update Your Cell Plan or Entire Strategy

Moving urgent calls and 2FA text messages to your flip phone and using only data on your smartphone has an interesting side effect:

Your smartphone could be data-only now. That changes the cellphone plan you need.

Unlimited text and calling for your flip phone could be $9 a month. You don't need to pay Verizon $80.

Good

Tello. It's cheap and it has worked. No issues with the portal or adding the SIM like other providers.

Interesting mention

Depending how much data you actually use on your smartphone (which is now a degoogled Pixel, right), a data-only SIM card could last you months before needing refilled / replaced.

Try running a super cheap calling and texting plan in your flip phone and a separate data-only SIM card in your smartphone.

Probably fine

Most MVNOs are probably fine. They're cheap enough it might be worth trying a few.

Avoid

I don't like the MVNOs who say they automatically switch which network they're using and then add fees each time they do that.

Especially avoid eSIMs. eSIMs are very software-centric. There's no physical card. Transferring them between devices may be possible but it could be more difficult or not possible depending on how your devices and network support that. There's also no guarantee that phones forget them when they're deactivated. A physical card you can remove and replace.

Cell Hotspot with Data SIM

Some degoogled android phone users go as far as keeping the SIM card out of their phone and using wifi only, even on the go.

Hotspots are small enough you can do that.

Good

GL.iNet GL-XE300 Puli (EC25-AF model for US folks).

It's easy to swap the SIM card. It has a big battery. It supports connecting to a VPN like Mullvad so you can run multiple devices on it instead of installing Mullvad on each one.

The data-only SIM cards are commodities. The only difference seems to be which location your traffic comes from when testing them without a VPN. If you notice the latency is too high, try a different brand.

Avoid

I'd generally avoid the hotspots that don't have a replaceable SIM or say they're otherwise locked to a certain carrier. Solis looks interesting but 1GB/mo feels low.