Half Price Books used to have two stores in Berkeley, one on Telegraph, a short four blocks from UC campus, the other on Solano Ave between the Oaks Theatre and Peet's Coffee. Both locations were odd-nook-and-cranny stores.
In the Telegraph Ave store you had two second floors -- one above your head as you came in, then there was a gap and another more substantial second floor began. Both second floors were served by separate staircases. The fiction room was in the back and down a step. It wasn't exactly a basement but felt like one.
The Telegraph store shut down a few years ago.
The Solano Ave store also had two storeys. Just inside the front door a staircase spiraled down past mirrors to the basement. Fiction and children's books were on the ground floor, everything else was snuck away downstairs and if you didn't have to brush cobwebs aside as you ducked toward the clearance shelves at the back you wouldn't have been surprised to.
The Solano store closed up and reopened downtown in the Kress Building. It looks like a Barnes & Noble or something. Everything is on one floor. It's airy, well-lit.
I hate it.