Amazon has a sturdy wall-mounted fold-out desk for $215 that also becomes a full shelving unit when not in use so you can ...

But if you're looking for a quicker solution, purchasing prefabricated shelves is a hassle-free way to get extra storage with plastic, wood, and metal variants. However, there remains the question ...

Both of these wood species have superb strength ... So, if you choose to maximize your garage storage space with plywood shelves, they will sag under a lighter weight than pine or oak ones would.