Where to order mobile phone spare parts from?

If you own a mobile phone repair store, where do you prefer to order your spare parts and accessories? Someone maybe order from domestic supplier according to their need, but for the people who want to order in bulk, maybe they would like to order overseas. If order from other country, which ones will you think about? Probably many people say China. Yes, China is the factory of the world, and Shenzhen is the electronic products factory of China. To choose your suppliers from Shenzhen is absolutely a good idea. If anyone is interested in this, please do not hesitate to discuss with each other here.