Shown on the listing. Keep it to what people need to decide; no explicit detail.
For a weekend or camp, set the last day's end.
The category is what a processor approved in writing. A charge only goes through a processor approved for its category.
Free only, for now:
The area is public. The venue is stored apart from the listing and released only to approved ticket holders.
Long-press the spot in a map app and copy.
Leave the venue blank if it isn't booked yet. Clearing it later removes it.