If you came of driving age in the '80s and '90s, you witnessed the rebirth of GM muscle cars. Pavement-pounding Turbo Buicks, sleek TPI and LT1 F-bodies, and 170-mph Corvettes led the charge, while wicked AWD Syclone and Typhoon trucks conquered the stoplight battles. It was a new performance era—a fuel-injected era—that seems like only yesterday.

But it wasn't yesterday—as hard as it is to believe, some of our cherished EFI GMs are nearly 30 years old. And just like you (and us), they've become classics.

If you've been keeping up with their values, you know that many have bottomed out, and are now appreciating. That can be good or bad, depending on if you are an owner or a buyer. But whichever side of the deal you're on, know two things: One, Internet car shopping is full of perils. And two, whether it's in your garage or in your dreams, you don't know nearly enough about that vehicle—or its value!

Let's say you're shopping for a low-mile LT1 Corvette, or one of 5,512 1986 GNs made. Chances are you'll visit some online "trader" sites, do some research, and run a Carfax. You've found a few possibilities, things are looking good, and you're starting to get excited. At this point, all it will take is a good sales pitch from an owner, and you'll gladly spend serious money to get the EFI GM of your dreams. But before you pull the trigger, answer this: how well do you really know this vehicle?

Now, let's turn the tables: say you already own a couple of valuable EFI classics, like an all-original Syclone and an LT4 Camaro SS. Life is grand, right? But think on this: if they're ever in an accident, will your standard, stated-value insurance (or the other guy's insurance company) give you a true market value settlement? And if you go to sell them for way more than the current book value, will you be able to get that price, and will the buyer be able to finance the deal?

Both scenarios are examples of what can happen, when the affordable EFI GMs we grew up with skyrocketed up in price and desirability. And that makes it all the more critical that you cover all of the bases when buying them, and understand their true value when owning them.

Thankfully, you can protect yourself, both before, and after the sale with pre-purchase inspections and appraisals.

Pre-Purchase Inspections

The pre-purchase inspection is a great tool for a car buyer. And it's especially important in the age of online car shopping. Because online car shopping is both the best, and the absolute worst; guys wanting crazy money for project cars, shady hustlers pushing chop-shop "beauties," and that one chooch with a "factory" 1999 LS6 Vette. Once you realize that there's no way you can make several long-distance trips to inspect your finalists yourself, you understand why it makes sense to spend a few bucks for a professional to inspect them for you.

"Our pre-purchase inspections help online car shoppers weed out bad examples," states David Williams of Auto Appraisal Network. "Lots of guys are getting sentimental and looking online for the car they owned, or wanted to own, years ago. And the best way to find a mechanically sound, good-driving vehicle is to have it inspected beforehand."

Appraisals

Just as a pre-purchase inspection protects potential buyers, an appraisal helps current owners, and their insurance companies, determine a vehicle's worth so there are no surprises if a claim comes up.

"Any time insurance companies are involved, a solid, thorough appraisal is needed to be able to prove what you have," David says. "And that takes a substantial amount of vehicle information."

Knowing an accurate value is great. But it's critical if, God forbid, you're ever in an accident in a "fault" state. You'd want the other person's insurance to pay, but even if it's their fault, it doesn't mean that their insurance company values your classic like your classic insurance company does. In this case, an appraisal would protect you from possible lowball settlement offers.

Appraising Your "New Classic" Late-Model Vehicle

Once you book an appraisal with a company like Auto Appraisal Network, appraisers at the home office will start researching the vehicle and its options. Next, a trained professional will meet up with you to visually inspect the vehicle—and they'll bring a camera, computer, and the requisite knowledge, of course. The appraisal may take several hours, with customized vehicles needing more time. Documents, awards, magazine articles, etc. will be documented, as will the vehicle's history from the original owner to you. Engine and drivetrain options will be verified, and the entire vehicle will be photographed to document its condition. Any differences between an original and a restoration will be noted. Major power options, like a power top, will be checked for operation, and the vehicle will be inspected for leaks. A test drive may also be done.

The VIN, cowl tag, odometer, and any other identifying numbers, like block codes, will be checked. And because newer vehicles have the longer, 17-digit VINs, appraisers get more info from them than from the older VINs.

"One nice thing about this era is the standardized, 17-digit VINs," David explains. "They give a lot more information, specifically digits 4-8, which decipher the drivetrain and body style.

"At the same time, some of the other IDs have become less important, but as these cars appreciate in value, someone will amass all the details specific to a collectible car of the period. I'm sure the information is there, but until the values increase it's not readily available." (FYI, David's site links to a popular VIN decoder; you can use it at autoappraisalnetwork.com/vin-decoder/).

The computers in our newer hot rods pose a challenge to appraisers. While some vehicles require a trip to a specialist, appraisers often can use portable diagnostic tools to determine if the vehicle is stock or modified.