Backup key storage at a central facility that can be ubered to you on demand. Solves the scale problem by centralizing it, and the cost + wait is limited to ube

Backup key storage at a central facility that can be ubered to you on demand. Solves the scale problem by centralizing it, and the cost + wait is limited to uber fare. In the end, it wouldn't work though because you'd need to charge a monthly fee and people wouldn't go for it. I lived in a low rise apartment before and just hid a key on the premises in a spot where it couldn't be associated with my apartment and that I thought wouldn't be likely to be disturbed.