I am traveling through Missouri soon and there are few charging options. I see a lot of RV parks though. I've never charged at one and am bringing the family. I'd prefer 50 amps because I don't want to stay long. My questions are: 1. Can I just show up without a reservation and charge my car? I've noticed none of these places answer their phone. 2. What charging cable do I need? I was planning on bringing my NEMA 14-50 adaptor and tesla charging cable, is that all I need? Thanks in advance.