Since it's used, do you know the amount of clicks (shutter count) it has? If the seller didn't mention that, maybe you could ask? There are tools online that can help you out.
If that number is reasonable and the camera looks like it's in good shape, i'd say go for it!
15-45mm lens on an APS-C sensor will add an cropfactor of x1.5, gives you a pretty nice range IMO, especially for day to day shots.