I'm searching for a phone which meets those requirements:
- Either below $100, or rugged (that is, I want to minimize cost of use. And I tend to drop things)
- No larger than 4.5", but the smaller the better
- Supported by current LineageOS (used to be named Cyanogenmod)
- Removable storage, i.e. uSD
While there are other requirements, I don't think there can be a candidate which meets the ones I listed, but not the ones I didn't list.