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."
Yeah. Nah that makes you sound silly (at least for software jobs) unless there is a good reason for it, like currency conversions or peverse tax incentives.
There is a tiny chance that asking for 133700 might get a smile at a smaller tech focused company though.
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."