Firstly, speak to the company on the phone. Can they sound like the kind of individuals you wish to entrust your computer data to? Good customer service goes an extremely long way, the company ought to be happy to answer your questions and explain inside non-technical language what their own processes are.
Second of all, do they recover the information in house? There are many those who claim to be data recovery specialists, but the proof is within the pudding and you should preferably look for a data recovery which can be fully equipped and has their own clean step facilities. Mechanically failed drives will have to be exposed and this should always be opened and worked on at school 100 clean conditions. Anything less may introduce contamination for the drive and drastically reduce recoverability, and in a few instances can cause irreversible damage, rendering your computer data lost forever.
Third, you should look for a company which offers a free examination of your device. Whether it's a USB flash drive or even a multi disk RAID array, any data recovery organization worth their sea salt will be able to assess your item and diagnose the fault, according to their extensive expertise. Some might point out there's no such thing as free, but a good data recovery organization that wants to work with you will usually not take a fee because of this.
Once the company has thoroughly inspected your drive or other press, they should then offer you a free quotation and also a detailed diagnosis in writing (via email is fine) so you can make an informed decision as to whether you intend to proceed. The quote should be itemised, accurate rather than subject to change. It will also be non-obligatory, so if you decide it's not for you, then you are not held to ransom and have the option of decreasing politely.
It should be stated here that expert data recovery is not a services that comes cheaply; this very often requires time-consuming and complex procedures, intense expertise often some in-house development and research to replace broken components and manipulate the firmware of your failing system, so you are therefore spending money on the company's skills, experience and time to recuperate your irreplaceable data, which in some complex cases can take many days to complete.
Another incredibly important thing to consider is whether the company offer a no-recovery, free scenario. Data recovery just isn't an exact science and sometimes, despite having the best engineer as well as tools, drives tend to be damaged beyond healing. When a company provides a no-recovery, no fee option which means that if they are unable to recover your data then there is free to pay.
It is all also easy to get stuck on who can provide the best price or a "one price fits all", but as this guide shows, once your data is at stake there are more, very important questions to ask to help you choose wisely.