Hi Sun Kim
This is an interesting question. My first instinct would to have treated each artifact as an asset rather than an item, but still you may have several of the same, so making them rotating would make sense as you can then track these individually. It also supports that last step of disposal.
At the end of the asset's life, you firstly change its status to decommissioned, then move it to a salvage type location. You can have many salvage locations to denote where it is at the end of life. Location names could be sold, scrapped, stolen, donated, or gifted. As part of the asset's specification, you can have an attribute to recognise the organization that you gifted or sold to, and the price. These can alternatively be simply fields.
A rotating asset, of course, can live in a storeroom and as part of the disposal process as described above, when you no longer are holding that as an item, you would go through the obsolescence process. But this feels like a double step as you have to firstly issue all the items to the salvage location, then obsolete the item.
A simple asset may make the most sense as the Decommission status takes the asset out of being selected outside of the Asset application.
You mentioned "inventory donations". You cannot tag an item with FMV as that does change. An item cost changes based on purchasing and thus updating the average cost, not quiet the same as the FMV at the time of donating. This is why I'm leaning towards an asset rather than an item.