How to display the number of contents of a node? We have a property site that we use to categorize our listings. I would like to know how to make each category show the number of content it has e.g. Sales(45), Lettings(20), etc.

Any help about how to do this? I am new to Drupal.
could you add some details to your question that will tell us WHERE you want to see these counts?   Is it in a page template? A view? A block?  The answer will change depending.

In the meantime, please look at this:
Count of nodes by type