Ah yes, Osman ... yours are the stuff of memories that we wish were ours too ...
Just to fill in the historical blanks, the Parmelia Hotel was effectively the 'one and only' until along came the much larger Sheraton Perth Hotel in the early 70s ... the former morphed into the Parmelia Hilton Hotel and it is currently undergoing redevelopment.
These hotels competed in so many ways, including their respective discos / nightclubs ... the Parmelia had Juliana's which was an intimate setting located deep inside the hotel ... the Sheraton had Clouds which had an entrance near Adelaide Terrace separated from the hotel lobby and which attracted a broader group of clientele. Back in the day, I'd never have considered getting a room ... silly me !!!