I would agree that the collar is the property of the Dominate. And when i seperated from my last Master we had a long discussion about my collar and what was to become of it. Ultimately i was allowed to keep it with the promise it would never be worn again. (And it hasn't been but is tucked away for safe keeping.) He couldn't see anyone else wearing it and it was such a strong reminder to the growth i had experienced from the relationship i hated to not have it.
Think the major difference is i at least had a say in it. Had he taken it back i would have been ok with that too, because i was given the chance for closure in a way and it wasn't just taken, with other items, out of spit, anger, etc.
As to him taking toys. Think that shows what type of man he is... so better to move on, even as painful as it is now, because it would/could be worse later! Not that i'm saying he wasn't entitled to some of the toys... but that again should have been a two way communication to determine.
Hugsssss... hang in there... give yourself time...