assuming it's the IS version i think you'd have no problems selling it for $80...if you need to you could always throw it on ebay...there's tons of idiots out there that pay more on ebay than it costs to get the lens new from b&h...
i don't really get why people are telling you to try it out...i'm sure they'd all rather have the 15-85mm over the 18-55mm
Yeah...and my Dad is bigger than yours...quite mature argument there.
I rather have L-glass than paying so much for someonelses opinion. I find my 18-55 quite sharp for my needs.