For the train station, it depends on when you plan to park. Nights and weekends, the lots adjacent to the station are open for anyone to park, AFAIK. Weekday/ work hour times require a parking permit. There are reasonably priced pay lots ($5-7 / day or something) across from the train platform, on the South side of the overpass.
Free parking behind Milford Library about 5 minutes away from station. One area for Milford residents but for non-residents the parking lot is behind tennis courts which are behind library.
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