If you’ve used a self-storage unit recently, you might be wondering why it cost so much money just for a place to put stuff. Experts say it’s a growing industry raking in billions of dollars a year from consumers.

But are they really worth the money?

Some people rent storage space because they’re moving into a new home and it won’t be ready yet, or maybe they need to get belongings out of the way because of a remodel.

No matter the reason, Kevin Brasler, executive director of Washington Consumers’ Checkbook, said they’re in high demand and very costly.

He told WTOP their undercover shoppers collected prices from self-storage companies throughout the D.C. area and found that, on average, even small units run about $900 a year, while medium-sized units usually cost more than $3,000 per year.

“Because they’re so expensive, the math really becomes irrational for most of those who rent self-storage units,” Brasler said. “Because just after a short time you’ll have paid more in rent and fees to that company than your belongings are actually worth.”

But if you really do need storage space, Brasler said be sure to shop around.

“We found there’s a lot of competition among these storage companies and they know that once they get you, once you move your stuff in, you’re going to be unlikely to move it somewhere else if you find a better price,” Brasler said.

He recommends asking for a discount, watching out for extra fees and making sure your homeowners or renters insurance policy will protect your belongings while in storage. Most policies will, but it’s worth checking first.

To save the most money, it’s best to just get rid of stuff instead of renting extra space.