|2006-Dec||0||Compact||35-140||Canon PowerShot A530|
|2019-Sep||2020-Jan||(2350)||1900||Canon EF||ILC||Canon EOS 5D Mark IV|
|2019-Sep||2020-Jan||(150)||140||Canon EF||Lens||40||Canon EF 40mm f/2.8 STM|
|2019-Sep||2020-Jan||(250)||250||Canon EF||Lens||50||Canon EF 50mm f/1.4 USM|
This is a table format that I use to track my gear, with some sample items.
Begin: when you got or bought or received in trade the specific piece of gear.
End: when you sold or traded the gear. If this is empty it means you still own it.
Buy/Sell: how much you paid or got for the gear. Zero means you received/gave it away as a gift. Sometimes you trade more for one, now you have to apply creative accounting and imagine how the trade was constructed. Usually bodies devalue more than the lenses. I mark these trades in parentheses.
System: camera system if it's a system camera or lens.
Type: compact, ILC, Lens, flash, whatever.
FL Equiv: fill this in and play in Excel to get funny graphs of your FL coverage. You can split the range into two columns, perhaps easier that way.
Gear: description of the gear.
In this example I bought Leica Q for $3k and then traded it for a 5Dm4 setup. That is implied by the dates and the parens.
In this example I own two cameras (or pieces of gear more generically), those that don't have an "End" date.
This is one way to keep track of your actual expenses because it's all bought minus all sold that's your expense for this hobby/profession. In my mind if you buy $3k worth of gear you're not $3k in the hole. The final cost is formed the minute you sell it for money probably less than $3k and you subtract what the gear actually cost you.
Further improvements possible:
I also mark in mine if it was bought brand new or preowned.
You may also expand this idea by describing condition perhaps.