I started off working in my personal Gmail account and now I wish to move everything into my Google Apps for Business account. I tried the following unsuccessfully:
Using the Share → Is Owner does not work—gives an error about sharing. Strangely then it works if you share between Gmail accounts.
I downloaded everything on PC drive, copied everything in another folder. Disconnected my personal account and connected to the business account. Then moved the contents of the folder to Drive and after re-synch, Google still memorised the owner and rights.