Yes, cocktail/ semi-formal. Any kind of bold, fall colors are welcome. No jeans, sneakers, sweatpants, and the like.
Yes there is parking. There will be people to direct you where to park. If need be there is a secondary parking lot. Also, handicapped parking is available if needed.
The ceremony starts at 4. I would arrive at least a half hour early if not part of the wedding party.
There are quite a few hotels around. Here are a few: -The Putney Inn -Best Western Plus Keene Hotel -The Covered Bridge Inn
Anyone that is invited is welcome to bring a plus one.