You have to pay some small entrance fee in order to visit the sacristy.
It’s not absolutely mandatory to do so, but that’s not because it is not beautiful. It is, albeit in all the splendor of the monastery, in a way the sacristy is just more of the same. A wonderful ceiling one more time, though not very different from that in the nave.
Here we see tasteful consistency again. Well, that’s what happens when a church is built in a relatively short time, and in order for this to happen, an enormous amount of money must be available 😄