Perhaps it would make sense to take a shelf out somewhere, or to add a sliding drawer to a cupboard below the counter. In closets, a second hanging bar can be added below the first one will double the hanging space, or shelves can be put on a side wall while still preserving the current hanging space. If you find it hard to imagine how your space could be reworked, take an exploratory trip to the local hardware or housewares store for some good ideas. Get your ideas, go home, make a plan and take measurements. Then go back to the store and get what you need.
Most homes have plenty of potential storage space.
Dave and I found room for a much-needed pantry behind the door of the back entry we share with a neighbor. Our tiny apartment has an unusually large foyer and hallway, which we've lined with Dave's enormous record and CD collection. Doors and walls provide particularly good spaces for storage. Shoes on inside of closet door. Canned goods on shelves that hang on the inside of the kitchen door Ties on a tie rack in the closet.