> And this has 4G/LTE (because it is a smartphone) so comparisons to base RPis are largely irrelevant.

Yes? So have countless new phones at around 150€. Including screen, battery, case, and warranty.

Edit: Just for fun, a list from a german shopping/comparison site, aptly named 'scrooge', selected for LTE, at least 2GB RAM, Octacore, Android 15 to not get too old stuff, in stock, 4 days delivery max, capped at 150€ incl. delivery. Sorted for lowest price first:

https://geizhals.de/?cat=umtsover&xf=10063_15.0~2607_2048~26...

Editoftheedit: To stay with the terminology of the 'largely irrelevant base RPI', they've built (or intend to?) a base board for whatever they are using as CM/Computemodule to plug into. I see some GPIO, some USB, one Ethernet.

A little bit of board layout, soldering of mostly passive components, and that's it.

Best of luck. (LOL)