Q. May one ask someone on Shabbos to open the Havdalah locker in yeshiva (where the items for Havdala are kept), if that person might not be around later and one needs the items for Havdalah?
A. There are two issues involved, one is Muktza and the other is Hachana or preparing during Shabbos for the use on weekdays.
Horav Shlomo Miller’s Shlit’a opinion is that since this is a standing on the floor locker, there is no issue of Muktza in just unlocking the door, since it also contains the permitted bessamim for Havdalah.
The one unlocking the door during Shabbos, should also take out then those bessamim and make a brocho before smelling them, to comply with the Meah Brochos, as others do on Yom Kippur. Since he is doing this on Shabbos there is no more Hachana.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a