Google Vision APIs

The client needs to build a system that is similar to Pinterest Image Matching feature. For this purpose, he wants to use Google Vision APIs. Please confirm if you have experience with the Google Vision APIs from before, and whether the APIs allow working with a custom set of images (matching an image with our own custom database of images) instead of Google's own database of images. Also, since the requirement of this app is in China, you might need to build the APIs on a USA server (as a proxy), and the final interface/app on china server because China doesn't allow accessing the Google directly. This project needs to be done on both Android and iOS. This project is from a trusted client. 100% milestones are created to me. However, the milestones for you will be created in 4 parts as the project progress as follows: Milestone 1: 25% milestones once 50% of the android app is implemented. Milestone 2: 25% milestones once 100% of the android app is implemented. Milestone 3: 25% milestones once 50% of the iOS app is implemented. Milestone 4: 25% milestones once 100% of the iOS app is implemented. However, no milestones will be released until the entire project is completed and delivered, and client is satisfied. Whoever bids 100000 INR or less will be hired immediately.