Size and function matter, too. If you're going to build a garage, make sure it will work as a garage. I see a lot of older tuck-under garages in Laurelhurst. I also see a lot of split driveway/shared wall garages. Many of these don't function as garages with today's larger cars. For some, even a Mini-Cooper is hard to get in/out of the garage and even harder to extricate yourself from the car once it's in the garage.
For location, it will depend on the parking and traffic situation in your neighborhood. If you're on Burnside, you're probably going to want a garage (or at least a driveway that will accommodate several cars). If you're on a wide open street with tons of parking, this is less imperative. I wouldn't say that having a garage on a busy street will give you tons of monetary value, but it will help a home sell faster.