Oh Regulus, sweet little Regulus, Sirius thought to himself. He hadn't meant Reg would literally own the place or the people, just that his music would be captivating. That kind of own was totally different. And Regulus didn't want to own anyone. Sirius could have hummed and skipped about. Those words meant so much more than Reg even knew, all things considered.
"We still have a little time," Sirius replied, about the music. Then he was a bit amused. "It took them a long while," Sirius replied to the question about muggles making things, "but they did it. They didn't know any other way. They didn't know there's an easier way." Really, muggles had done a lot without magic, including making this place.
"You don't have to go," Sirius replied with a grin. The question about meeting people here was more for Remus to answer. If they used magic, it was sure likely possible, but it wasn't the lesson Sirius wanted to show Regulus - to manipulate muggles with magic to get what he wanted.