If you plug the cable into your PC in a USB port, the photos should automatically transfer to you PC.
I would have folder ready to store your ebay photos, so that you can quickly find them.
You will get a prompt, asking you what you want to do once the PC recognises your phone.
I'm unsure how it would work on an ipad.
I have a Samsung phone and the charging cable can be used, no need to buy a separate cable.
The only problem I have found is my phone keeps locking if I go away and leave them downloading, so I have to keep unlocking it.
You can also do that to get rid of all your sent Whatsapp photos , rather than clear them on your phone, if you run out of memory.
Good luck!