Is there a parking facility around? Is that free?

There is a lot of parking at the arboretum. The first parking lot is near the visitor's center. Then each section of the park has parking.

Yes. By the visitor center.

Yes, parking is free at the Arboretum. Check the website as the R Street parking lot entrance is closed to entry vehicles at certain times.

There are a number of parking lots inside the Arboretum, all of which are free.

Yes

Yes. There is ample free parking.