With the right tools you'd be amazed what is recoverable. Unless you are doing 7 pass wipes of your free space with CCleaner or something comparable, it is still on the disc.
Firstly, ensure you go to the 'right' company to do this, it probably won't be cheap. This will be the difference between All/Most/Some/None of the files recovered.
Secondly, stop using the laptop now. Chances are that all that has been genuinely overwritten is just the OS and applications sectors of the hard drive. Even a 'real' format just changes the tables and leaves the actual files on the disc. Using the laptop will be creating new files over the old ones, potentially making the old files unrecoverable.
You can download stuff to do this yourself, and you'd be fine for sure, but with it being uni work, I'd strongly advise against that method.
For my uni work I have everything in DropBox (which mirrors to two PC's as well as their cloud) and I have an Apple Time Capsule). That probably really isn't enough, but it does me ok. Strongly advise that your friend moves to more sensible data backup.
Go for a simple option, even if it costs money. I sorted my mum out with full cloud backup of her entire PC for something silly like £20 a year. Sure, it costs £20 and you could do it for 'free' with some old PC kit, or hacking together various applications, but ease of use is so important these days. USB key fobs are NOT data backup in my eyes, they are far too prone to breaking or getting lost.