Some people choose to use Hospitable, formerly known as Smartbnb, to handle messaging. Hospitable can be used in conjunction with OwnerRez, if you set it up correctly.
The only adjustment you'll need to make is with your automated messages. If you choose the "Jumpstart" onboarding option during your Hospitable account setup, automated messages are enabled. This could cause a duplicate new reservation message if you already have that message configured inside OwnerRez.
Since automated messaging is the main reason someone would use Hospitable, we suggest configuring your Hospitable messaging and then disabling your automated messages inside OwnerRez. This way you will not be sending out duplicate messages.
Here is the document Hospitable provides: https://help.hospitable.com/en/articles/5268781-i-m-already-using-software-can-i-still-connect-to-hospitable-com