I think the listing is fair priced.
waiting little more into the middle of winter, where people sell their bike cheap (cheapest during the year) is another idea. GZ250 is usually more expensive than GN because of the fancy suit, but by middle of winter GZ and GN 250 shouldnt have that much price gap
Don't forget you will need at the very very least 3-400 bucks for gears too. 200 for new helmet and rest for 2nd hand gloves, boots, jacket and pants maybe?
Just don't think you will dwell forever on your first bike and spend more than your budget, I'm sure you will want to change your bike soon enough.
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