Here is one top tip from the Chris Voss book: Don't ask for a round number. If you ask for a more precise number it sounds like you have done more research etc.
EG Not: "I've looked at my finances and similar roles, and I need $130,000 for me to take the role."
Instead: "I've looked at my finances and similar roles, and I need $133,700 for me to take the role."