Sofas, dining tables, chairs: These are the pieces you’ll so often find labeled as “investment furniture,” those pricier objects that take center stage in a home and are loved and lived with for a lifetime. They accompany you through new jobs, moves, and maybe even relationships. Even if it comes time to downsize, they aren’t the pieces you shed. But say your space is tiny, you live in a city, and you really love organization: Enter the modular shelving unit.

Yes, high-quality shelving should be near the top of your “buy this and keep it forever” list. In fact, it can be considered the very best investment piece for small spaces or renters—it holds up in the face of heavy, you can always break down and reassemble it in a new home (even in a new configuration), and while it’s there to be a keeper-of-things, it looks like a design object itself. Plus, while you can certainly justify splurging on a modular shelving unit for all the reasons above, you don’t have to—scroll down to read about our favorite picks at a variety of price points.