Also there is no connection between a wallet and an address except the wallet stores the address. When the client sends the address the change is returned to a

Also there is no connection between a wallet and an address except the wallet stores the address. When the client sends the address the change is returned to a new change address, and the wallets are being designed now to never reuse addresses. So it would become very hard to determine which of the outputs are change addresses and in the same wallet.