Ok, you will want to add a new "player spawn join" event.
In the conditionals
PLEVEL=1
(Only if you want new players only, or leave it blank for all players)
and in the script,
move {player_steamid} -1000 -1 -1000
sayplayer {player_steamid} "Welcome, you will be automatically teleported to the safehouse." or something similar.
(-1000 -1 -1000 being the coordinates you want the player to go.)
EDIT, I just read all players. Plus I didn't do it right anyway. It is correct now.