The Supply Depot is the place that agents can get standard issue supplies, general things like backpacks, restraints, cards, field-safe food, mini care items, standard exorcism items (sorry, no eight pound bells), uniforms—basically anything that isn't considered a luxury item and isn't covered by DoSAT or the Armoury.
The Supply Depot is run by Kelemen Totth, who has a possibly Transylvanian accent and is a sort of cross between Mr. Homn and Hagrid in appearance.
The door to the Supply Depot opens onto a small waiting area with a few plastic chairs. A large desk blocks off another area, just big enough for Mr. Totth to maneuver in. Behind that is a curtain. No agent knows what exactly is behind the curtain. Mr. Totth keeps a book that lists standard supply lists for all mini types (apparently it updates itself when new minis are discovered). He has an amazing memory for agents names and faces, and is able to remember vital information such as department, division, and number and type of creatures living the agent's response center on their last visit.
Mr. Totth notes the agent's requests, then disappears behind the curtain for varying lengths of time. He eventually returns with all items in cloth bags marked Supply Depot. These bags can be returned by agents. It makes Mr. Totth happy.