There is none
Press the back button.
on your map perhaps?
You dont unlock houses like you do in saints row 1 you have to go out and buy them. They will be marked on your city map. -Nolan02 =)
It is in the white zone(saints row district)
Bottom left of the map ;)
press the button next to start
on the map there will be a house sigh go there and pay for it
There are five currently, Saints Row, Saints Row 2, Saints Row: The Third, Saints Row IV, and Gat out of Hell.
They removed them from Saints Row 3. You can only get them in Saints Row 1 and Saints Row 2
Yes, you can free roam over the entire city map.
It should be marked on your mini map or the bigger pause screen map, I don't remember the color but the legend of the map should tell you.