The cost of installing five windows falls somewhere around $5,000, or about $1,000 per window. If your garage doesn't have any windows, plan to add at least one. This is especially important if you want to list it as a bedroom or rent it out. You'll need an egress window big enough for a person to escape through in case of a fire. Egress windows average about $3,500.
For a garage-to-utility-room conversion, budget at least $6,000 for appliances, a utility sink, and space for sorting, folding and hanging laundry. A new utility room in place of an old garage brings convenience into your life, especially if you've spent years dragging loads of laundry up and down the stairs. This conversion will cost a bit more due to the addition of plumbing, but it'll be worth it.