I suspect that when you get home with the 18-55mm you're going to discover in short order that the 55mm reach isn't enough for many things. Then you'll start wondering what zoom to get and how far that will need to go.
I lived with an 18-105mm on my D7000 for 2 years and it was fine for 95% of what I shot (that didn't require a 150-500mm for wildlife, that is). An 18-140mm would have been even better. I've spent the last week walking around with my 24-120mm on my D7100 and it's about perfect for everything I want to do with walking around, street photography. Add a little more at each end and it would be even better.
So, what I'm saying is, spend $200 now and avoid the nerve-wracking guilt and beating yourself up over not doing it 2 days to 2 months from now when it hits you that the second lens is going to cost you more than that, and now you have to swap when the one is out of range.