If you are working as a freelancer creating an iOS application that won't be published on the App Store, can you use your personal Apple Developer credentials, or does the client have to provide their own Apple Dev account credentials?

saw this thread here https://developer.apple.com/forums/thread/131013?page=1#665205022 As a developer I am primarily interested in the new LiDAR enhanced AR capabilities of the new iPhone 12 Pro and iPad Pro. The question is, which has the better LiDAR scanner? Trying to make a purchase decision but can't seem to find the specs anywhere. Are they both identical?