Garages may have started out as a place to store cars, but gradually they’ve become a place to store almost everything else, from sports equipment to dog food to holiday decorations.

As the weather gets warmer and the spring cleaning urge hits, it’s a good time to take stock of your garage. Is it a functional space or just a repository for junk? Are there more logical ways to store your belongings?

Before you rush out and buy new shelving and cabinets, professional organizer Cindy Tyner recommends putting some serious thought into how you want to use your garage. She says the No. 1 mistake people make is pulling everything out of the garage first and then getting overwhelmed when they try to cram it all back in.

“People go out and buy things, like storage systems and bins, and say, ‘This is what I need to get me organized,’ but the things don’t fit the purposes they need,” said Tyner, who owns an Ann Arbor, Mich.-based organizing business called Functional Spaces.

Once you’ve decided how to use your garage, here are some tips to help you finish the job:

• Pick a sunny day and clear out all your belongings. Decide what will stay, what can be donated and what should be thrown away.

“If you haven’t used it in a year, you need to ask yourself, does it make sense to keep it? If it’s important to keep it, how can you use it? If it’s a family heirloom, should it be sitting in the garage where you can have a variety of problems and moisture?” said Sean Hunt, president of Garage Specialists Inc., a San Bernardino, Calif.-based company that cleans and organizes a few hundred garages a year.

• Once the garage is cleared, sweep and wash the floors and walls. A fresh coat of paint can brighten the walls, and paints made especially for garage floors protect them from oil and gas stains, and prolong the life of the concrete. Home Depot, for example, sells 1-gallon cans of Rust-Oleum Epoxy Concrete Floor Paint for $31.97. A gallon covers up to 400 square feet.

• Consider what kind of storage you need. Costs vary significantly, from $40 plastic shelving to $350 steel shelving. You can use old kitchen cabinets or buy new ones. Gladiator GarageWorks, a division of Whirlpool Corp., makes heavy-duty plastic tracks that run along the wall and can be fitted with cabinets, hooks or baskets. A two-pack of 48-inch-long tracks is $29.99; a six-pack of bins that fits into the tracks is $14.99.

Kris Nielson, the CEO of Monkey Bar Storage, a Rexburg, Idaho-based company that makes steel shelving systems, said people can spend up to $10,000 on custom garages with fancy flooring, refrigerators and other perks. His company, which has 68 outlets in the United States and Canada, charges an average of $1,500 per garage to install steel shelving systems, which he says are designed for durability and efficiency.

“This is not your dining room. It’s your garage,” he said.

• Use all your available space. For items you only need occasionally, such as holiday decorations, consider overhead storage units. A 4-square-foot Racor platform, for example, holds up to 250 pounds and can be lowered with a cable system. Hyloft makes a smaller, less expensive overhead storage system, measuring 45 square inches.

If you want a workbench but don’t have a lot of room, consider one that folds into the wall.

• Store things close to where you need them, and in logical places. All the gardening equipment should go together, for example, and the bike helmets should be next to the bikes.

“Everything has got to have a home. Otherwise it just gets piled up and it’s a snowball effect,” Hunt said.

• Store some things outside. Consider a deck box for children’s toys or a storage shed for gardening tools. Lowe’s sells Rubbermaid’s Roughneck storage shed for $299, for example. Tyner says you just need to make sure to use the new space properly and don’t let it become your new catchall for junk.

• Consider hiring an organizer. Organizers can give you good ideas about how to use your space and keep you on task as you’re trying to decide what to keep and what to toss. Costs vary by region and project. Organizers will charge you more, for example, to buy and install storage units than to work with units you already have.

Hunt said his company will fix up a garage in a day for an average of $1,500 or so. They also come back and do tuneups when you need them. Tyner gives free 30- to 60-minute consultations and then charges $40 an hour, although she notes that organizers’ rates vary widely by region.