A lifetime licence covers one domain. An agency licence covers ten. You can add more at $49 each.
We do not check whether you own it
Deliberately. Scanning a competitor is a legitimate and common use, and there is nothing confidential in a scan. Everything we look at is publicly published. What your licence limits is how many domains you track, not whose they are.
Changing your domain
Before your first paid scan: free, as often as you like. A typo should never cost anything.
After it has been scanned: changing it uses your one change for the year. The screen tells you this before you confirm, never after.