Scanners have dropped in price a lot, so now we see ones designed with a specific purpose in mind. This is as if you are a scanner manufacturer; you can offer your scanners less to people who do not need a function by not putting it in.
If you buy a scanner for the back office, when they use it on the front counter, you may have problems. This is because many back-office scanners have a button to press to activate them. This works great for people who only need to scan occasionally. For people on the front, they find it a pain to keep pushing the button for each sale.
The reverse can be true too. Front counter scanners often have a bright laser. In the back, it often gets directed against their eyes. This is because they do not have the scanner beam positioned away from them as it is in the front. This is actually dangerous.
Many scanners can be programmed to overcome these problems. The problem here is that programming them is a real pain and requires a person who knows what they are doing.
So please let us know precisely what you need.