Try to avoid buying or accepting a used crib. Older models may not meet current safety standards or may be in disrepair. If you must use an older crib, avoid those built before 2000, about a year after the latest voluntary standards for slat-attachment strength took effect.
What kind of crib do you want? Do you want a crib with both sides that drop so that you can get your baby from either side, a crib with one side that drops, or one with stationary sides? Deciding first about drop sides will narrow the selection and make shopping easier.
When you're shopping for a crib with drop sides, operate them in the store to make sure they raise and lower smoothly and quietly. Models that open with a lift-and-leg-press action or those with a lift-and-foot-release mechanism can usually be operated with one hand. Remember, once babies get bigger and stand up in the crib, you can pick them up without lowering the side. So a crib that doesn't have the best drop-side mechanism but is satisfactory in other ways can still be a good option.
The simplest in-store test is to shake the crib slightly to see if the frame seems loose. But be aware that display models aren't always as tightly assembled as they could be. Without applying excessive pressure, try rotating each slat to see if it's well secured to the railings. You shouldn't find loose bars on a new crib.
In the store, pair the mattress and crib you plan to buy to make sure they're a good fit. (Mattresses typically are sold separately.) By law, a mattress used in a full-size crib must be at least 27 1/4 inches by 51 5/8 inches and no more than 6 inches thick. Still, do a quick check. If you can place more than two fingers between the mattress and the crib frame, the fit isn't snug enough.
When looking at cribs, it is difficult to discern quality differences from brand to brand. You'll find a lot in different price ranges. The pricier models are sturdier and more decorative than economy models. They come in an array of wood finishes, from Scandinavian-style natural to golden maple and oak shades, reddish-brown cherries, and deep mahoganies. End boards may be solid and smoothly finished, and many models have slats on all sides. The gentle curves of the end boards are well finished with rounded edges. Slats are thicker and may be round or flat, with rounded edges. The mattress supports on these models tend to be sturdy, the springs heavier. These cribs have single, double, or no drop sides. Locking wheels or casters provide stability. There may be one or two stabilizer bars--metal rods that extend between the two end rods--running underneath for greater rigidity. The best-made cribs in this category have recessed guides--a grooved channel in each end board for the drop side, no exposed brads or glue residue where the slats are fastened to the rails, and a uniform finish. They may have extra-high posts, canopies, or a storage drawer underneath.
You'll also find cribs that convert into other configurations. One type, typically called a 3-in-1 crib, converts to a daybed and to a full size bed. You'll also find 4-in-1 cribs that convert to a toddler bed, a daybed, and a full-size bed. The most versatile cribs can become a toddler bed, a full-size bed and a love seat. For any budget, these are great options, because you will not have to replace the crib with either a toddler bed or a full size bed once your baby is big enough to sleep without the crib.
