The biggest advantage to buying a refurbished laptop is almost always the savings. You're giving up the privilege of being its first owner and unboxing it fresh. That might not be a huge deal, but you have to understand what "refurbished" means for the seller you're considering. 

A "used" laptop is generally sold in the condition that the previous owner left it. A professional refurbishment, meanwhile, should involve an inspection, cleaning, testing and repairs. Unfortunately, the standard for this varies across companies.

Dell and Apple, for instance, both have a program selling refurbished laptops. Apple's Certified Refurbished products undergo testing, arrive in a new box and come with a one-year limited warranty. A retailer selling its own refurbs might offer a shorter warranty with less guarantees, so you'll need to check what's covered. Generally, refurbs by the original manufacturer or a reputable store are safer than some online repair shop you've never heard of, though there are many places to shop refurbished tech.

Alternative statuses include open box options, which were usually returned and never used, that can shave off a few dollars. There are also specialist refurbishment companies that will repair and resell laptops. It's worth considering these if you don't find what you're looking for elsewhere, especially if they're transparent about their testing and repair process.

There are fewer guarantees when you aren't buying from a big company, but you can at least run through a few standard checks. Look for a seller who explains what's been tested, with clear condition grades that spell out the wear you should expect, along with an idea of the battery's current condition. Photos of the actual machine are useful, especially if there's any visible wear or tear. 

Unfortunately, you're limited on how much you can check yourself unless you're able to physically inspect before you buy. If you can, ask to switch the laptop on and try it out. Otherwise, ask for pictures and videos, including one showing the serial number, if you can. The return policy is important to consider too: what are your options if there's a problem?