Leave the car standing longer – what to do?

Hello, I have the SL 560, from the end of the 80s. I would like to hear from you your experiences what it is like if you leave the car untied for a long time. What should you do with it no or little damage? I think that there should be enough gasoline in it so that nothing dries out in the tank of seals or what rusts; disconnect the battery; park dry and cover. One does just that, the other does so. But what would the facts be more correct 🙂 I red e park here already really from a long time. Maybe even unsubscribe, since it does not really make any sense financially. That would be months if not more than 1 year. Evtl also has information about parking possibilities to itself (Room Berlin). I wanted to hear from you before I contact Mercedes Benz directly. I thank you already for your experiences.