It's free for home / personal use and uses Peer to Peer technology
One concern some may have is this was formerly BitTorrent Sync and is built on BitTorrent technology
Sync only transfers data by establishing a direct connection between peers you select.
Sync data is encrypted in transit and keys are all stored locally (no cloud)
As I said, several Maccast users say the use it and love it, so this might be an option.
Purging Time Machine Local Snapshots
Play tip from John
In case you weren't already aware… if you use Time Machine and are disconnected from your Time Machine volume Time Machine will still run but save the backups locally to your hard drive if there is enough available free space
Only runs if there is at least 20 percent free disk space
System see the space used by local snapshots as "free" space
You can also delete these manually via Time Machine, but it's not as easy as the [DaisyDisk](https://daisydiskapp.com) method
1. Open Time Machine preferences from the Time Machine menu in the menu bar. Or choose Apple menu > System Preferences, then click Time Machine.
2. Deselect ”Back Up Automatically” or click the Off/On switch, depending on what you see in Time Machine preferences.
3. Wait a few minutes to allow the local snapshots to be deleted. Then turn on Time Machine again. It remembers your backup disks.