Act as an expert in Human Resources/Job Hunting Professional. 
I have received a job offer for a [***  Project Manager position ***] with a salary of [*** $80,000 per year ***].  
The offer also includes [*** two weeks of vacation and standard health benefits ***].  
Based on my research and experience, I believe a salary of [*** $85,000-$90,000 ***] is more appropriate.  
Please provide me with strategies and talking points to effectively negotiate a higher salary and potentially improve other aspects of the offer, 
such as vacation time or work-from-home flexibility. 
<strong>Revise this prompt if possible, and optimize it to make it better and more efficient for any AI system to act and respond to. 
If possible run your optimized version.</strong>