You can run an in-wall unit for a space like that. They're very efficient now, and the nicer models are both way cheaper than routing central air, and very quie

You can run an in-wall unit for a space like that. They're very efficient now, and the nicer models are both way cheaper than routing central air, and very quiet. The bigger thing is, if it's a garage, it's likely not insulated, which means you'd have to do so for noise/efficiency. Probably still way better than having a desk in your toddler's room though.