In this 1945 city directory for Miami, among the entries for the surname "Rosenthal" is the following entry for Albert and Naomi [Harold's parents]:
Albert I (Naomi) ship clk Sunny Palms Sportswear r1606 Meridian av apt 94 (MB)
I think this indicates that Albert was a shipping clerk at Sunny Palms Sportswear, and that he and Naomi rented at 1606 Meridian Avenue, apt. 94. I think "MB" stands for "Miami Beach." A slightly different address (1600 Meridien) is listed in the 1945 census form.
Another entry for "Rosenthal" is the following:
Albert mgr Lincoln Terrace Apts h1606 Meridien av apt 4 (MB)
It would be quite a coincidence for there to be another Albert Rosenthal in the same apartment building -- so perhaps this means Albert (and Naomi?) were managing the apartment building in which they were living?