Possibly buying my first Rolex

[09cs]

Hi everyone! So I may be buying my first Rolex and would love some advice! It is a Submariner (standard black one, no date)

It is from a very trusted dealer by me, it is a 99-00 model, and is asking for $5700. I'm not sure where to start with this so I'll do my best

• Price? Is this a good price for a 17-18 year old sub?
  What to look for when seeing it in person?
  Does box/papers/tag affect price? I would like to have all that, or at least the box
  Lume- I'm assuming check to make sure it all lights up

Anything else to look for?

Thanks in advance!