Hello, I am trying to help a family member set up and use their new Mac. I see that Yosemite has the ability to screen share, but it appears to be limited to Macs on the same network or on the same Apple/iCloud ID. It looks like Apple Remote Desktop would work, but it costs $80 and it seems like overkill. Does anyone have any suggestions on who to share screens with two Macs over the Internet and with two different Apple/iCloud ID's? Thank you.