Some questions about Shenzhen?

You can find a job online and go to Shenzhen again when you have the opportunity. Cheap ones are Baishizhou and Dachong.

The conditions are ok. It depends on your standards. Baishizhou and Dachong rent a single apartment for 500 ~ 800, which is nearly twice as expensive if it is a residence.

If you eat, you can usually eat fast food around 10 yuan, and you can cook by yourself. Many friends buy food and cook by themselves after work in the afternoon, and bring the food back to the company the next day, so the cost will be lower.