From what I have seen so far, it is generally the more expensive salon software systems that offer integration with hardware such as barcode scanners.
There are two main types of salon software available at the moment - firstly stand-alone systems, which are generally more expensive and often require significant capital outlay or a credit/hire-purchase/leasing agreement, and may have specific hardware requirements such as a particular type of touchscreen, till, barcode scanner, etc - and secondly online systems, which often run in a web browser (thus alleviating the need for expensive hardware purchases as they should run on any computer with a broadband connection) and are often priced on a subscription basis - thus avoiding a large initial outlay or getting locked in to a credit or leasing agreement.
Operation wise, there are advantages and disadvantages to both. With the stand-alone system, it is often you who is responsible for data back-up - you would need to ensure that you make regular back-ups in case there is ever any problem with your computer's hard drive. Whereas an online salon software provider would store your salon's data on their computer system, and would be responsible for backing it up (so you would need to make sure that they have a good back-up strategy in place).
What you may need to do is to prioritise your requirements for what you want your salon software system to do - so ask yourself what are the most crucial elements of the system, and which could you do without for the time being. If the barcode scanner was a "nice to have" rather than a necessity, then you may be able to save money by opting for one of the cheaper solutions that doesn't support a barcode scanner.
Also, ask each company what they offer in terms of support, and if there are any ongoing fees (particularly important if you purchase an expensive system) - also how willing would they be to add new features to their system to support your needs if you particularly want your software to do something but their system currently doesn't?
Probably one of the best things is to do a search on Google for salon software, as there are a lot of providers out there at the moment.