Depends on how it crashed. Sometimes the bearing on the motor seizes up, the heads can actually break and crash into the platters [worse kind of crash] or something burn up on the circuit board, tons of different things.
Sometimes, if it's a seized bearing or dried-out bearing, which is very common, if you wrap the drive up tight in a zip-lock bag and put it in a freezer for a few days, then take it out and hook it up in a computer, it'll start and you can get your info off of it. With a seized bearing, the drive will usually just make a 'click' click' sound. A sharp smack on top of it with the palm of your hand while it's hooked to a computer and the drive's first trying to initialize will do it too sometimes, with a bad bearing, but you risk knocking a head into a platter doing that. If you do this, get all your data off it right away and don't shut it down until you do, it may not startup again!
A bad circuit board can be swapped for a good one, but the donor drive for the board has to be the
exact same type/size drive, most times the drive's firmware needs to be dumped and flashed to the new board too, the same goes for swapping platters from one drive to another and it should be done in a clean room environment, but it can be done elsewhere if you're careful and don't intend to use the drive after you've recovered your data. I wouldn't recommend doing that unless you play around with a lot of junk drives and get a idea of what it involves, it's real easy to get your fingers [thus grease, other contaminants, etc] onto the platters or scratch a head across one of the platters and ruin it. If it needs to be sent out to a clean room, it will be expensive.
Seeing as how the tech told you they didn't even know who/how it could be recovered, I wouldn't put much faith into their diagnosis of it, it may not even be crashed, maybe it's just a software issue like the FAT is screwed, the OS took a dump, or something that was beyond their capabilities, or that they just didn't want to be bothered with fixing. It's a lot easier just to throw in a new drive and clean OS install and call it a day, rather than muck through someone's drive with who knows what on it, or try to fix something they have no idea of what the problem is, way too many computer "techs" do this.
Does the drive still spin up when it's installed in a computer or is it dead, dead? Does it click, does it smell burnt, what OS was installed on it? What model/brand drive is it? What model/brand computer was it installed in when it failed? Did you try it as a slave/second drive in another computer with the same OS to see if it could be read at all? It's been a long time since I've done any drive recovery work, but there use to be some decent and easy to use recovery software available for a few hundred dollars, many had trials that would let you try and see if it could recover anything and list what was recoverable, so you didn't have to blow your money for nothing, if the drive still spins up. It's been too long for me to recommend anything, a good fifteen or so years, but I imagine software is out there still.
like others have said...anything important, back it up and then back it up again somewhere else, and keep backing it up!
