This is how you get ripped-off folks.  This is exactly how NOT to go bike shopping.  This is how to insure you get the LEAST for your money:

http://buffalo.craigslist.org/mcy/1063371697.html

Shoot...I'm gettin out the circle saw, boring out the old gs, making some tin can rings and making $3500 

Odds are, it's far more likely to be a scam than a guy with $3500 itching to buy a bike, ya know?

If it seems to good to be true, it's from Nigeria...

I've spoken to some clowns like that. Beginners with no more than 2500 and want to get a good beginner bike 600-750 CC no less.
OK Pitch the $1500 GS idea and you'd get laughed at.
Ask them what they want, they'd be like GSXR or CBR 1000 less than 2-3 years old, with low miles. WTF ... that sheite costs 5K if it can be that cheap.
One clown bought a 2500 buck YZF 600 ~99-00 which has been stretched and lowered, and did not run. Its comming over tommorow with a laundry list of To do's including change tires and do brakes. You're aware that this is not running right ... OK. You want a tune up. Aaaaaah OK what is a tune up. I dunno man you're the mechanic. WTF ... Maybe change oil. So that's going to make it run. I dunno, you're the mechanic, It needs a tune up. OK ...
Cool.
Buddha.

Well bo the brakes, tires, oil change, and other odds n ends and then tell him well that's not the prob.
Lets see maybe we need a new motor or maybe a flux capacitor 

and the blinker fluid as well as the nos bottle for the rear tire

and make sure he knows you have to change out the winter air for spring air in his tires

the guy is putting out feelers so what?