Before buying a larger drive, identify what has filled the current one. Use the operating system's storage view or a trusted tool appropriate to your system, and inspect categories without deleting anything immediately. A growing original photo library is a different problem from several forgotten copies of the same export folder.
Write down what must remain readily available, what can be archived and what is genuinely temporary. These categories should describe your workflow, not simply file age. An old project may still be active, while yesterday's preview files may be reproducible. Confirm dependencies before removing application-managed data.
When capacity really is the constraint
If the collection is legitimate and continues to grow, estimate that growth from recent months. Choose enough room for the period you want the new drive to serve, plus the working space your applications need. Plan the separate backup at the same time. Expanding originals without expanding their protection can leave the newest material outside the backup routine.
Check the cost of the complete move: drive, suitable connection, any enclosure and the time to copy and verify. Make the new destination clear, and keep the old copy until the transfer and updated backup have been tested.
When another drive would repeat the confusion
If you cannot identify the authoritative version of a project, more space may simply preserve more uncertainty. Choose a small, representative project and document its original, working and delivery folders. Resolve that example before attempting a whole-library reorganisation.
For apparent duplicates, compare more than filenames or thumbnails. Two similar images can have different edits, metadata or resolution. Keep a backup before any duplicate-removal process and review its selection criteria. A large automated deletion is not a sensible first response to an unclear collection.
If the real problem is slow access, trace the connection and application behaviour. A larger drive does not automatically improve a limited port, a faulty cable or a catalogue stored elsewhere. Record the specific delay you want to reduce so you can test whether a proposed change addresses it.
Finish with a small plan containing separate actions: organise a defined folder, remove only verified temporary material, expand storage where needed and update backup coverage. The purchase may still be necessary, but it will then serve a known job rather than postpone the same decision until the next disk fills.
Resolve one ambiguous folder before a large cleanup
Suppose three folders contain a presentation with similar names. Open the files, inspect their dates and contents, and ask the people involved which version was delivered. Save the confirmed version with a clear label and preserve the others in a temporary review area until you understand whether they contain unique material. Do not let a duplicate finder make that editorial decision solely from names.
Once the rule is clear for that project, apply it to a small group of comparable folders and check the result. Keep an action log for moves and deletions during the cleanup. The log need not describe every file; it should let you explain what changed if a missing reference appears later.
Only estimate recovered space after the reviewed changes are complete. Then compare the remaining collection and expected growth with available capacity. This order prevents a new drive purchase from becoming a substitute for identifying what the collection actually contains, while still allowing expansion when the files genuinely need it.
