The issue is with the Insert Record server behavior. If you don't see it in the Server Behaviors panel, it might be because of hand edits preventing Dreamweaver from recognizing it. It looks like you may have removed a few line breaks... try updating lines 102-116 to:
GetSQLValueString($_POST['Description1'], "text"),
GetSQLValueString($_POST['ForSale'], "text"),
GetSQLValueString(isset($_POST['ContactPermission'])?"1":"0", "int"));
mysql_select_db($database_conn1_i, $conn1_i);
$Result1 = mysql_query($insertSQL, $conn1_i) or die(mysql_error());
$insertGoTo = "boat_insert_images.php";
if (isset($_SERVER['QUERY_STRING'])) {
$insertGoTo .= (strpos($insertGoTo, '?')) ? "&" : "?";
$insertGoTo .= $_SERVER['QUERY_STRING'];
}
header(sprintf("Location: %s", $insertGoTo));
}
?>