First of all, the data isn't being inserted because there is no data.
Notice the error? "VALUES ('', '', '', '', '')' at line 1 "
Does '' look like your data?
Double check the field names. Also, are you sure you are POST'ing these variables from a form?
Also, without quotes (i.e. $POST['test']), you are telling PHP to look for a constant. It will usually fail and fall back to using it as a string, but still, you should use quotes in your $POST[] statements, such as:
if(!get_magic_quotes_gpc()) {
$MLSNum = mysql_real_escape_string($_POST['MLSNum'], $connection);
$Address = mysql_real_escape_string($_POST['Address'], $connection);
$Desc = mysql_real_escape_string($_POST['Desc'], $connection);
$Price = mysql_real_escape_string($_POST['Price'], $connection);
$Ph1 = mysql_real_escape_string($_POST['Ph1'], $connection);
} else {
$MLSNum = mysql_real_escape_string(stripslashes($_POST['MLSNum']), $connection);
$Address = mysql_real_escape_string(stripslashes($_POST['Address']), $connection);
$Desc = mysql_real_escape_string(stripslashes($_POST['Desc']), $connection);
$Price = mysql_real_escape_string(stripslashes($_POST['Price']), $connection);
$Ph1 = mysql_real_escape_string(stripslashes($_POST['Ph1']), $connection);
}
$sql = "INSERT INTO FeatProperty (MLSNum,Address,Desc,Price,Photo)
VALUES ('".$MLSNum."', '".$Address."', '".$Desc."', '".$Price."', '".$Ph1."')";
NOTE: I also added some escape functions to help protect against SQL injections. Also take sarain's post about column types into consideration.
EDIT: Also note that indeces of the superglobals ($REQUEST, $GET, $_POST, etc.) are CASE SENSITIVE:
$POST['foo'] is not the same as $POST['FOO']