You might think you don't need a workshop, but you'd be wrong, dead wrong. When the day comes, and it will, that you wish you had a workshop you'll understand. In the future adding a workshop will be extremely expensive, and it will mess up your home for months. And in the end it will be a compromise between what you wanted, and what you could "fit" into your home. So, make the smart move and build your new home with a workshop from the get-go.