One day I’ll split it up, but I have one large catalog stored on Dropbox. This allows me to use my desktop or my Surface Pro and keep the catalog synced.
The photos themselves are stored on a network drive organized by year and date.
The network drive is synced to a large internal hard drive on my desktop every 4 hours via SyncBackPro.
Then some of the folders are synced to Dropbox, and some folders are synced to Google Drive - just because I could only get 1TB from Dropbox.
I also have Google Photos scanning the internal hard drive for the jpgs and uploading those as compressed high resolution files so that storage is free and unlimited, for quick access, not as finals to be sent to anyone. The real finals are in those Dropbox or Google Drive folders.
Oh, and that internal drive is backed up to an external drive daily. So all in all, I have 3 hard copies, 1 cloud copy of the originals, and 1 cloud copy of shareable compressed jpgs for each photo.
I intend to update all of this to a NAS and still sync to the cloud services in the future, but just don’t have the funds right now.
Feel free to ask me any questions on the Dropbox set up or using SyncBackPro, I can’t recommend it enough. Never had a bad sync or corrupted files in any of this… knock on wood.