If I don't want to generate a lot of mess, broken glass and heavy metal residue, does anyone have a recommendation for an affordable service to securely shred old devices in a trusted and transparent way?

Commercially I've used some of the bigger services, but at home I have a growing collection of old phones and hard-drives which are too broken to easily recover, and so need destructive erasure.

I don't really trust the "just drop it off with some big corp" approach, and would rather somewhere that is more transparent.

Basically looking for the Iron Mountain "we shred it in front of you" type deal, but for non-big companies.