I have been using an Excel Spreadsheet Workbook, creating a spreadsheet tab for each major manufacturer or Manufacturer Series like: Britains - ACW, Britains - WWII, etc.
Then within each tabbed spreadsheet in the workbook I created column headers as follows for example:
Mft.; Period; Series; Cat. No.; Name of Set or Description; On Hand; Paid Each; Retail Each; Replacement Value (On Hand x Retail); Status (NIB, MIB, Exc, Good, Fair, etc.); Num. of Figures (in Set); Issue Yr.; Notes.
Then I created a Total or Summary Spreadsheet that gave me a Summary of each Mft./Category with number of Sets, Replacement Value, Number of Figures.
Included in the Summary sheet is sum number of volumes in my Reference Library and Library Replacement Cost, also totals for Diecast Military Aircraft Model collection, Toy & Model Soldier Collection, Non-Military Figure Collection, War-Gaming (15mm) collection, War-Gaming (25/30mm) collection, Militaria & Masonic Collection.
With each entry or change within an individual spreadsheet, the Summary sheet is linked and is automatically updated. When I go to a Show or see a figure or vehicle for sale, I can immediately see if I have it in my collection or make note of it for future purchase or consideration.
Wall art (e.g. paintings) is not included in this workbook.