THE FIRST THING TO KNOW
Before starting you have to know that this is a job that must be done by a professional, is not a DIY task, the professional need to analyze what kind of noise is the one that can be noticeable and according to that, choose the right material (there are so many types of materials that can be used to soundproof an area).
But this is very useful not only for reducing the noise from outside but as well to improve the sound inside the room, for example, imagine a conference room or a theater, this can be a plus in those kinds of rooms, normally they are used for conferences, meetings, and all these meetings have in common the use of a speaker and sound, so the acoustical environment is the perfect complement, sometimes can be as useful as no microphone will be needed.
BUYING THE MATERIAL
It is very important that before buying anything, quote in different stores, not to buy in the first one, compare prices and the relationship between cost and quality if you need to ask for the advice of an expert, look for a company, you can read the comments of the clients, look for recommendations, and as well compare prices, not always the most expensive is the best if you do not have recommendations, look for the reputation online and check the social media profiles.
Normally the installation companies are the ones in charge of providing the material, and as well check if the person that is going to work in your company has all the personal safety equipment, if not you are in the right of demand it, this can save you future problems.
Once the company had finished asking for the maintenance procedures, and how to take care of them, also is good to ask for the guarantee and have clear the times in case you need it.
This investment is something that for sure you will never regret; the results are immediate and last for several years.