Q. What is it supposed to be on the show? A. A residential home.  Q. Where is it supposed to be on the show? A.  In or near Miami, Florida. Q. When did we see it on the show? A. We see it first in Episode 2, of Season 1, in a scene where Harry drives Laura back home after recruiting her as a police informant. That's when he first meets little Dexter & Brian. We see the house again in Episode 4, when Harry and his partner Bobby go to her house to pick up Laura, and Harry winds up babysitting her two kids, then later in the same episode in the scene where Harry discovers Brian torturing lizards. And it turns up again in Episode 5, with several interior scenes of Harry bonding with Dexter and Laura. Q. What is it actually in real life? A. A residential home.

Q. Where can I find it in real life?

A. This house is located at 11143 Tiara Street, in North Hollywood.  

It's a modest two-bedroom home at the northeast corner of Tierra St. &  Fair Ave.

The early shots of the home's interior and backyard appear to have been shot at the actual house.  But if they continue to use Laura's home, they will no doubt build a set at the studio to duplicate its interior, as they did with the Morgan family home.  

North Hollywood is not what it might sound like to non-locals. it's not the north side of Hollywood.
 
Rather, it's a completely different neighborhood located on the other side of the Santa Monica Mountains, on the east side of the San Fernando Valley. 
 
But it does have its Hollywood connections. The Academy of Motion Picture Arts &  Sciences has its headquarters there, and NoHo (as it's called) is only 2 miles away from Universal Studios Hollywood, Warner Bros. Studio, and Disney Studios.

Q. How the heck did you figure out where it was?

A.  In several exterior shots of the house in Episode 4, when the actors are in the porch area, one can clearly see the street number just under the porch light: 11143.

And one good thing about large, five-digit street numbers is that there aren't that many of them in Los Angeles (at least not compared to three-digit street numbers, which can we found in virtually every community). In short, the larger the street number, the fewer the homes, and the easier it is to pinpoint the exact location.

I knew that they had been filming mainly in Long Beach and in the San Fernando Valley (where their new studio is). I didn't believe there were any 11143 house numbers in Long Beach, so I started looking in the Valley, and found it reasonably quickly.    

Here is a StreetView from Google:

 
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