Ah, I see now. Thought it was too good to be true!
If I don't have a WAAS source already, it would be $3,795 for ADS-B out (and I could use Stratus/Foreflight for ADS-B in). This is probably what I'd do.
And again, if I won't have WAAS already, it would be $5,795 for ADS-B in/out in one box...