No, thanks. I'm just browsing
No, thanks. Just looking
having a look around
window shopping filling the time
I'll call you over if I need you.
Don't like the colour / the size.
It's not the right color / my size.
The price is too high. I have to watch my budget. I can't afford it right now.
It's not what I exactly want.
Not ready to buy it right now. Will think it over.