Ciao @Amos19 , I saw your CIN code is already mentioned on your listing.
The other requirements related to the use of CIN are:
- a sign of your CIN code on the entrance to your accommodation on the public road, mentioning “Locazione Turistica” (generally it is a metal sign measuring 3 x 10 cm if there are no particular municipal rules). 
- safety requirements:
- 6 kg fire extinguisher on each floor for every 200 square meters (with a certified maintenance plan)
- gas and carbon monoxide detector in every room that has gas burners or wood fireplace
You can find the FAQ here on the official website of the Ministry of Tourism:
https://www.ministeroturismo.gov.it/faq-banca-dati-strutture-ricettive-bdsr/