Pan has stayed in service apartments on the mainland, and feels that the biggest difference is cultural.

"Chinese buildings are newer and better," he concedes. "But many cannot handle English well. The staff tends to be more judgmental. If I'm in a t-shirt, staff in China will stop and question me. In Hong Kong, they recognize our need for discretion.

He feels that Hong Kong service apartments can improve on language skills, too. "If you don't speak Cantonese, it's a problem as most people don't speak English."

Shanghai native Yu Shuangshuang has lived in Shama Fortress Hill since arriving in Hong Kong last August to begin her studies in business administration at HKU Space.

She shares a one bedroom apartment with a girl from Hangzhou who is in the same program, and attends classes across the street in the campus above Fortress Hill MTR station.

A family friend in Hong Kong helped her find the apartment. She says: "My friend thought Shama was better value for money compared to similar places in Tsim Sha Tsui."

According to Marilyn Fu, director of sales and marketing for ONYX North Asia, Shama's parent company, 75 percent of residents stay in Shama's five Hong Kong properties for less than a year. In the predominantly residential community of Fortress Hill, many locals who are renovating their homes will relocate in Shama for a few months to avoid living among construction chaos.

"The longest stay resident is more than 10 years," says Fu. "We have observed that more mainland tenants are staying with us."

Yu knew about Shama already, as the brand opened its first mainland Chinese branch in Shanghai's Xintiandi district in 2007.

"It's convenient to stay in a serviced apartment as everything is included."