If your hard drive is damaged, or encrypted, it will need to be sent to a lab to retrieve the data. The lab employs specialists who perform data recovery. The special lab for damaged drives must be free of all air contaminates while they carefully disassemble hard drives to retrieve the data platters. They then place your data platters in a working hard drive and attempt to retrieve to your data.
If the surface of the data platter(s) is scored, it means that the head has crashed into the platter while it was spinning and scraped off the magnetic coating. The magnetic coating contains data. In cases like these, recovering data is not possible.
Data Recovery Lab costs: When a drive must be rebuilt with new parts you need a Certified Clean Lab. A single hard drive recovery from a lab averages about $1800. Prices vary to extremes between labs and the kind of recovery.
Be wary of labs offering tempting, low flat-rates, and be especially wary of any lab advertising $199 recovery. If you carefully read their terms, you will see there are many reasons they can and will raise the price after you send them the drive. Your final price may match or exceed that of a reputable lab.