First of all, you don't need to give any advance notice of your arrival here. You just call to Port Moselle on VHF 67 before you enter the marina. Of course it's wise to call early enough because the marina is normally almost full. Some people also just anchor near Port Moselle and give marina notice about their arrival.
We got berth there and it was really easy to check in. We filled few forms in marina office and they called customs, quaranteen and immigration and informed them about us.
Soon 2 guys from quaranteen came to our boat and just asked few questions and took all our fresh food away.
Customs never came to our boat and we heard it's very normal here.
Woman in marina office just told that we have to wait them 2hours and if they won't appear, we can leave from boat.
Immigration was closed already (they close at 12) so we went there next morning. That visit was also short and easy (we filled that one form in advance).
So checking-in is very simple and FREE:)