Maintaining a small amount of incidental resources is fairly easy. You might not need to do anything if they are all expendable, if they have been depreciated down to nil value, or if their value is below a set value (e.g. $1,000, $5,000) and the accountant doesn't need to list them as an asset.
A larger inventory, however, is quite different. Some organizations have millions of dollars worth of assets that are not listed in their asset registers. Some even lose track of blocks of land.
You will need a computerized inventory that works, and that matches the size and sophistication of your organization. Depending on your needs, it should have systems for:
This becomes even more complex when assets are spread over several locations.
In many matters you should be conferring with a qualified accountant.