Negotiating first academic appointment (letter of offer) [duplicate]

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• Evaluating and negotiating a start-up package 1 answer

I am a physician who completed a postdoc recently. I have been offered an academic position at a different university, but the letter of offer does not specify any research time. It is my understanding that this will be the only time i will be in a position of power to negotiate something, but i dont know where to start.