A D&D sorcerer is supposed to have a source of their magic, right?
What if it’s Geoff? Geoff just… doesn’t have time for adventuring anymore. Has a collection of artifacts, but you know, family has to come first. The best stuff is on display, but some is in storage. If an adventurer wants to borrow magical power, then sure… but only if they bring it back later! Just part of being a good neighbor.