Semi formal- preferably no jeans
No it will be towed. Try to use a taxi, bus, or Uber.
If the invitation was address “and family” then yes if it was only addressed to you or me and mrs then please no extras. If you have questions please talk to Samantha or Marshall.
Yes! If you do not RSVP then plan on bringing a sandwich and chair. The venue and menu are planned in advance and they both need to know in advance.