Answers

1. We can use the AddTransient method.
2. We can use the NotFound method.
3. We can use the BadRequest method.
4. The problem is that buildingDescription in the request doesn't match the name of the Description property in the model. If the request is changed to have a description field, then this will resolve the problem.
5. We can add Required attributes to Code and Name as follows:

   public class BuildingPostRequest
   {
       [Required]
       public string Code { get; set; }
       [Required]
       public string Name { get; set; }
       public string Description { get; set; } 
   }

6. We can use a Range attribute as follows:

   [Range(1, 10)]

7. The HttpPatch attribute can be used to handle HTTP PATCH requests.