Two bedrooms and 2 bathrooms I think is always a must have when buying. Also since you are thinking of having kids, I would be looking for a townhouse and ruling out a condo. Transportation costs are also a huge consideration and it sounds like you are concerned about that, because you are worried about moving to far away from the city.
Doing the saving and having all your ducks in a row so you are ready to go is something you can control. So you need to know how much of a mortgage you can qualify for and that sort of thing so that if some great deal comes along you are ready to pounce on it. You also have to be fine with the market diving once you do make your choice, make the deal and move in. You can't control what the market does except make a great deal for yourself and live with it.