I remember pretty well that I have seen a movie like this on television. American, extremely well produced. Should be between 2005 and 2012.
A woman, hot and confident, tries to take revenge on a gang who killed her parents.
I don't remember too much information. The woman knew how to use many types of weapons and seemed supernaturally strong in the movie.
I don't remember that she had anyone fighting with her against the gang.
I think the villain had sharks in his home (put in some aquarium outside).
Somewhere in the movie I remember when the girl got sad about her parents.
Ending (99% sure): The director makes you think that the villain escaped in a car, then it turns out the woman had kept her violent dog in his car so that he would rip him up and kill him.