I hate "let's just have a quick call" people. It's never quick, it's always manipulative, and always a waste of time.
I have a client who tries to use calls to weasel out of paying for things. Finally I refused to talk to him on the phone any more. Some invoices remain outstanding but I'm not willing to waste more time listening to BS. I can spend my time making money from responsible people and meanwhile continue to have my invoice system pester him.
Re: sales, there is no such thing as a quick sales call.