Honestly it depends on what you are looking for. Since "best" is a relative term, it is important to understand what exactly you want your new property to be, to give you that best answer. For example, if you are looking to be in the Beverly Hills High district, then some of the "best" streets would not be an option, as the cutoff for the district does not extend into some parts of the hills. Also, if you are looking for a larger lot that is more secluded, you would likely prefer to be up in the hills, which may put you outside the desirable BHHS district. If you have children and plan on having them attend BHHS, then you would need to limit your search to just certain other "best" streets.
That being said, a few popular streets include Mapleton Drive, N Carolwood Dr, Benedict Canyon, Rexford, Mulholland.... really it depends on what you are looking for. If you like, I can provide you more specific information on some of the properties located on these and other desirable streets. Feel free to get in touch with me!
Alan Kurpiewski, REALTOR
CA BRE Lic. 01912043