Fortunately when everything is complete we would only need to focus on upkeep and maintenance, but it would be nice if we set a system in place now to avoid pain down the road.
I personally like Ansible especially when going from manual to automated as you can incrementally add to it but get using it quickly. Overall Ansible is pretty simple and it is super flexible without adding unnecessary complications. You can have it run your tests and make sure they all are passing before it moves the new software as live.
Plenty of consultants are available and can set it up for you if you need it done fast or it really isn't hard to learn if you have a little time.