I feel a person should be comfortable asking for money, even big money – whether it be charges against one’s services or donation for some cause or a wife asking from her beloved husband or whatever. One should be child-like while asking. Asking requires one to shed his sense of somebodiness, sense of identity.
Introverts have a worse time asking for money than extroverts. It’s a limitation they should learn to get over. I am one and so I speak from experience. While I have come a long way, I have a long way to go yet. My current role model as regards this aspect is Osho.