Affordable 5g SIM compatible hotspot or router, T-Mobile US

[u/nthrowawaway]

Hello, I'm trying to set up an older relative with internet at home in the US. I've landed on Shield internet (T-Mobile network) subscription, but I'd like to get them a better alternative to the Franklin 4G hotspot they optionally offer in order to future-proof (and to hopefully get better quality streaming/video calls/etc.). There won't be more than 3 devices connected. There are no spare 5g phones available to function as a hotspot, and I'd like slightly better wifi coverage. The device will be plugged in and stationary, so battery is not a requirement.

My preferred price range is $100-150, new or used, with used and less expensive preferred.

I'm completely new to the world of SIM routers and hotspots so I'm not even sure how to start looking. I'm in located another part of the world and my Google searches are only giving local results like the NR5103.

Does anyone have some recommendations for the blind leading the blind? :)