Is it worth all the time, money and work?

Now is a very good time to add on to your home. The bank interest rates are low. The advantage in adding on to your home, instead of purchasing a new one for example, is you know what you have in your home, the neighborhood, family friends, mature landscaping. Familiarity is valuable. There is no familiarity in purchasing a new home, since you have no experience with it. Anything you do to an existing structure, will make it better, larger, and more valuable for the future.