How should i negotiate salary?

Well i received an offer of 64k-69k and the HR rep said they will try and shoot for the higher end. i was hoping i could get 70k-75k how can i ask for this without blowing my chance at this job? i did do some research and 69k seems to be at the lower end of the average salary of the area i am going to, median is about 71k. also what extra things could i tag on to my salary to make it worthy? they do provide things like health care and dental, maybe i should ask for more vacation, flexible time, over time, company car or what?!?! this would be my first civilian job, but i have way more experience than what is needed. if i cant get the 75k whats a reasonable price that i can offer that wont scare hr away or make me look bad?
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Tell them that you are willing to hear what their best offer for you is. If it seems reasonable to you, take it or work it out if you feel that you qualify for more. Since the median is around 71K, you should shoot for a salary around there and work it out from there.
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