Argument 2: cannot convert from 'method group' to 'int'

Cannot apply indexing with

Cannot apply indexing with

Cannot apply indexing with

Cannot apply indexing with

Cannot apply indexing with

Argument 2: cannot convert from 'method group' to 'int'

Cannot apply indexing with

Cannot apply indexing with

Cannot apply indexing with

Non-nullable property 'Rent' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Client' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'SmartPhone' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Return' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Name' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Email' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Phone' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Rents' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'stockName' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.