"Isn't it just crazy? A fat guy who's nearly 50 goes out, plays the saxophone in the park and hopes to be a singer before he hits 60."

After work, she goes back to the rented one-room apartment on a noisy street because, though shabby, it is warm.

Her employer Ruby Zhang says she values Shen's help. "She is very patient and caring with the children, cooks delicious food and is meticulous with the cleaning. The kids love her."

Shen says she is happier in her current job than she was in the last one, where she had to work harder and the pay was not as good.

Earlier she worked for three years, in a ceramics company in Foshan, Guangdong province, as a quality inspector.

"I had to lift ceramic products weighing more than 50 kg, from the ground to the work table and check the quality. When I left that job I could lift 300 pieces a day."

She was paid about 3,000 yuan a month, but it left her exhausted every day, she says.

Later she came to Shenzhen and worked as a saleswoman in the delicatessen of the French supermarket chain Carrefour. The job was easy and she was happy, she says, because she could make friends. But she quit after six months because of the poor pay, 1,800 yuan a month.

Ai Xiaoxiong, general manager of Zhongjia Homemaking Group of Shenzhen, one of China's biggest home services companies, says demand for quality domestic helpers is rising in cities.

Salaries have increased greatly, almost 10-fold in 10 years, he says.

"Families in a city full of migrants need domestic helpers to take care of their babies and the elderly, and to clean the house or cook."

There is no shortage of work or of home help, and Ai says his company can put domestic helpers and prospective employers in touch with one another nationwide.