Nothing in this title contained shall affect the power of a person, although insolvent, residing either within or without this state, to transfer property in this state in good faith to a particular creditor for the purpose of paying or securing the whole or a part of a debt owing to such creditor; provided, that joint, or joint and several, debtors can prefer their joint creditors only out of joint property, and can prefer the individual creditors of each only out of the separate property of each.