I have noticed here in South Florida that many businesses will give better service to someone on the phone then to someone who is physically present . I guess the thinking is that if you are there you will definitely buy something. But the person on the phone needs to be courted if you will. I resolved the problem by calling from outside the store on the side walk and then entering the store. The employees look amused and sometimes annoyed! but it works for me.
Sometimes you are sitting with a chap in his office, working a deal with him, when the phone rings. What does he do? He answers the phone and works a deal with that person on the phone! There you sit ignored looking at whats going on and wondering perhaps I should phone next time!