We have tags for the cases with some basic info.

We keep the Typewriter Databasethe Typewriter Database current.

And we have a spreadsheet that tracks details:
Link to TWDB
Ultra/Standard/Electric Portable/Manual Portable
Good or Needs Work
Similar to another model or Unique
Brand + Model + Nickname
Decade + Year made + SN + Country Made In
Body Color + Body detail
Key Color + Key detail + Key Layout
CPI + Typeface + Ribbon/Spool notes
Case + User Guide
Cost + Shipping + Purchased from details (where, who)
Repair dates and cost
2 potential Values - low and high
Given/Sold to + Date + Cost

We had the spreadsheet and the tags early in our collecting, we just tracked more info as the numbers got higher. The TWDB project we did in stages, getting the machine data in first then uploading basic pics, going back to update typeface samples, more pics then links and updated descriptions. I still have galleries that need updating...

Very few can I tell from their case what's inside.

I love looking at the galleries in TWDB and reading descriptions about original owners and how machines were found etc.