Indeed, that is certainly high-quality. Nevertheless, it is very formal, as an example with letters having to do with legal issues. A lot less formal and much more normal is "Expensive Sir or Madam:" (Notice the usage of the colon; "To whom it might concern:" also must use a person). https://propertylawyerinkarachi21648.blog-a-story.com/17711704/a-review-of-top-advocate-in-karachi