I'm getting ready to purchase a new bicycle for myself, but am in desperate need of some recommendations. Though I have ridden bikes my entire life, up until this point it has been on BMX/freestyle bikes. I'm getting a little old for that but still would like to be able to ride for recreation and exercise. I live in a city environment and don't really see myself taking my bike on much if any trails, however I would like the ability to cut through grass or go up or down a curb if the need arised. As I said, I will mainly be using this bike to go for rides in the morning for exercise.
If at all possible I'd like to spend less than $300, but if I have to I could go up to $500. I know this is asking a lot, but I'm kinda strapped for cash at the moment. Any recommendations at all would be greatly appreciated.