The Baltimore street-cars I remember from when I was very young were the Witt cars (photo courtesy of M. E. Borgnis):

While they were introduced in the 1930's, there were still a number of them in service in the late 1950'a and early 1960's, especially on the southwestern side of the city. My recollection is that you entered at the front and exited at the center. Originally I think there was a motorman at the front and a conductor at the center, and you paid your fare at the center. By the late 1950's the fare box had been moved to the front next to the motorman, as the system had gone over to one-man operation (which was better accommodated by the next-generation cars).
Regardless, my most enduring memory of the streetcars was my grandmother yelling at me to keep my hands inside the windows. I don't recall attempting to hang out the windows, but she lectured me endlessly on the fact that one could get their arm torn off by a brush with a utility pole. Adults could be such joy-killers.
No. 6146 was manufactured by Brill and entered service in 1930. Here it is seen at the Belvedere Loop in 1950.
There's an urban myth in Baltimore that the street-car tracks were simply paved over after the conversion to buses, and that street-car service could be easily reintroduced by clearing away the black-top that entombed them. In fact a high percentage of the trackage was torn up, either immediately or over the intervening years.
Healey