Metro round trip would cost $12 for one person? That seems high to me.
Springfield Metro to Navy Yard for one person round trip (assuming the highest Peak of Peak prices), plus a potential parking fee of 4.50. It can get close to $12. It's less than 12/person when you bring 2 or more because they don't include parking, assuming you take one car.
Edit: Springfield to Navy Yard Round Trip (PoP one way, Reduced fare back) + Weekday parking = 12.45, or 7.95 for each additional person. It'll be even cheaper on the weekends, 5.50/person.
