'Restored' seems to get tossed around alot. I've seen many claimed restorations that were little more than a new paint job. Ideally a quality restoration will bring the vehicle back to the same condition it was when it left the showroom floor. This will generally mean a complete rebuild from the tires up. Expensive process and usually reserved for vehicles that can generate a sizeable return on the money spent
Anyway...it's pretty easy to tell how good a job was done just by doing a casual inspection. Look for areas difficult to clean or repaint...this will expose how much effort was put into the project. Dirt and grit in places like the top of the trannie or transfer case, behind the exhaust manifolds, etc will give a good idea of how deeply involved the process was. Aftermarket goodies are a sure sign that the restoration is really in name only. Doesn't mean it's not worth buying but it's certainly not worth paying extra for simply because someone claims the vehicle has been restored.