@soccercrazy

I´m not a Union Berlin supporter but I recommend to built the "Alte Försterei". There is no stadium in Germany which is as beautiful as the "Alte Försterei" and the Union Supporters often create an atmosphere the famous Fans of Dortmund, Schalke or Mönchengladbach only can dream off.
Besides I think it´s an advantage for a stadium builder if a stadium only has one stand with seats.
Fritz Walter Stadium, Eintracht-Stadium and the Millerntor would be great choices, too.