Plans (US): 15GB for Free, 1.99/Month for 100 GB, 9.99/month for 1TB, 99.99/month for 10 TB
Pro Indexes images
You can search images by object, place, or face when they've been added to your Google Photos collection. Google Assistant also helps you find screenshots that could be archived, images that aren't in the correct orientation and pictures that would work well as animations or albums.
Con Terms and Conditions allow Google to own anything on Google Drive
They can create derivative works, they can perform it, they can modify it, and they can publish it at will. There are many other specific rights they take over your product. Read the Terms carefully and compare with ANY others.