Actually the 18-55mm IS worth less than $100 as many pple are offloading their kit. I wouldnt be surprise that you will be stuck with your kit lens if you are selling @ $120 and above.
Well. If the kit costs $1100 with lens and $1000 without, then you are getting the kit lens for $100.
For starters, even if you got
none of it back you're still getting good value compared with almost any other lens out there. You get to use a lens with a good range of focal lengths, with quality and attributes that are perfectly alright for someone starting out.
Let's say a year down the road you decide to upgrade, or give up photography. Yes maybe you can't sell it for $120. (if you ever could then there are a lot of silly buyers out there - and also another point, some people clearly think it's worth paying $120 for a second hand version for this so why shouldn't you pay $100 for a new one?)
But is it the biggest disaster in the world if you don't get $100 for it? Even if you only got $50 for it you'd still only lose $50 for the privilege of using it for a year. That's absolutely nothing.
Sometimes, and I am not referring to anything within this thread specifically, but I do wonder about the photographic culture in Singapore. Buy very expensive stuff and expect to sell for silly high prices - get real people.
Buy your stuff to use it, not to worry about whether it's still shiny enough at the end of the 2 years you've had it so you can try and get 95% back of what you paid for it new.