Have had

[jack]

What do these mean?
1. Have you been there before? (Is this asking about if you have been there in the past?)
2. Have you been there?

I reply back with:
3. I have not been there before. (Does this mean that you haven't been there before? And now you have?)
4. I have not been there. (What does this mean?)

[Casiopea]

1. and 2. are synonymous, and 3. and 4. are synonymous.

'before' is implied by the use of the perfect structure 'have been'.

Q: Have you been there (before; i.e., in the past)?
A: No, I haven't (been there (before)).
A: Yes, I have (been there (before)).

With 'yet', the speaker assumes that you made plans to go, and s/he wants to know if you actually went or not.

Q: Have you been there, yet?
A: No, I haven't (been there (yet)).
A: Yes, I have (been there). *'yet' is not required with a positive reply.

[jack]

Let's say I'm at that place right now and I say:

Q: Have you been there (before; i.e., in the past)?

1. I have not been there before. (So does this also implies that I have been there now?)

[AintFoolin]

if you are currently at the place you are discussing, you would say "Have you (ever) been HERE before?". Here, not there, and the 'before' is no longer optional.

possible responses:
"Yes, I came here last week"
"Yes, I come here often"
"A couple of times"
"All the time man! I love their chicken wings!"
"Nope, I've never been here before"

[Casiopea]

Let's say I'm at that place right now and I say:
1. I have not been there before. (So does this also implies that I have been there now?)

In addition, if you are 'there', then use 'here':

Q: I have never been here before, have you?
A: No, I haven't (been here either).
A: Yes, I have (been here before).