It is VERY inconsistent.
I've been in older (pre 1930's) homes with both in-ies and out-ies.
I've been in new construction - again, homes and apts/condos at all price levels - with both kinds of doors, whether single or double.
Even including those built post 1999 to Miami-Dade building codes (they have the strictest building codes, enacted after Andrew, and builders in Broward and Palm Beach counties will often use that as part of their marketing spiel - "up to MaimiDade code standards" ).
I just found this. Interesting about the doors in home in the north.
http://answers.yahoo.com/question/in...4134132AAnjQK0
Makes perfect sense.