Have her visit Oldehopefarms.com - the farm is on the Eastern Shore of Maryland. Jane Ward has been hosting unrecognized events there for years and her Oktoberfest has become a destination event for riders at or below Novice. She generally caps her big shows at 250 entries, but has taken a few more.
She has I believe, 5 dressage rings and jump levels from Greenhorn through Novice. Everyone parks in a huge field across the street from the actual farm. She has maybe 6 stalls, and generally does not offer them out unless someone needs to stay overnight. Everyone shows out of their trailers and brings their own water. She has water at her barn, and of course it's available to use, but it's a long hike with heavy buckets. Just pointing out that having people bring their own can be successful.
Schooling is available and she also does a lot with local pony clubs and offers overnight vacations for kids - it's really a great place.
This is very exciting! I could certainly see a lot of interest among people who are located in South Jersey. But it might be a challenge to bring people over the bridges, when there are already so many good XC schooling and showing options for people who are in MD, PA, and DE. Location is everything, though. Is the site very close to a bridge and highway? That might be enough to draw people, or it might not. We have the struggling Dream Park show facility, which is pretty well located but not necessarily well utilized, as a possible caution (although this may be more of a management issue than anything else). Your friend might want to touch base with Country Haven, which offers lower level XC schooling (in Woodstown), to see how much interest it attracts.