Looking to buy new 350z! Just a few questions, help me how ever you can please!

So I just got a new job that will allow me to make enough for a 350z. I was originally looking at a G35 but I've always dreamed of owning a 350z. So my question is where I live, a 2003-2005 350z with anywhere from 55,000 miles(the lowest I've seen) upwards of 100k+ miles goes for anywhere from $8,500 up to around $20,000. OR in my area there is 2005-2008 350z's in the area of $10,000 to around $15,500. My original budget was $10,000, is it worth a little bit extra say $15,000 for a 2007 350z? Please let me know! also do you think that a 350z sounds like the right car for me? u