Hi.
You probably need a couple of Arrays (preferable
Array Maker List).
1 for position
1 for rotation
1 for Scale (if you can scale items)
1 for the object reference (name or Id number for example)
To save them its probably best to get Easy Save or a other saving asset.
you can find actions to save array lists on the Ecosystem.
if you want to use Player Prefs you need to split your arrays into separate variables as playerprefs save is very limited.