Is 'there' correct in the following case?

Experts,
I've asked a similar question before, but please allow me to ask again.

I'll be at home, call me there.
I'll be at my office, call me there.
I'll be at John's, call me there.
Let's say that you're leaving a message that you will be at a certain place later on and asking someone to give you a call at that place while you are at that place, is the word 'there' proper?

I'm at home , call me there.
I'm at my office, call me there.
I'm at John's, call me there.
Similarly, you're leaving a message saying that you are at a certain place now and asking someone to give you a call at that place. Is word 'there' proper? Or should it be 'here' instead?

Thank you so much.