i'd love to hear what details you keep track of and how!
for me, some of the most useful data are:
\- source (e.g., online platform or person's name)
\- estimated fill level at time of acquisition (i often get partial bottles)
\- cost/mL
\- bottle's full volume
\- size (sample, mini, travel, full)
\- dispenser (atomizer, splash, dabber vial, applicator wand)
\- date decanted
\- date gifted or returned to someone
\- date emptied