Best bet is to take an Uber or a Lyft. They are the cheapest options if you are staying here
The Metro Rail maybe the best and least costly option based on traffic...
Any time here is tourist season, but more so during the summer. The subway is nearby, but will take atleast 30 to 45 minutes with changes. It would be the least expensive with a day pass or discounts, but more hectic with a child, daily travelers and tourists. Take an Uber or Lyft as suggested. You can call, prepay in your card and go.
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