Running a business efficiently means having a way to record everything, including sales and stock. This is usually done through a database, so when looking for a business web hosting company, it is very important to bear this in mind.
The first thing that you need to consider is the type of database that you have. Some will run on SQL databases and others will opt for Access. Not all hosting companies are able to offer something for both of these options, which could cut down your list of companies by at least half.
If you do find that this is the only thing that is stopping you from choosing a company, then you could consider changing the type of database that you are using. You will need to make the decision about which is the best for your business and whether you have the time and patience to transfer everything onto another database system. Remember that this could also mean learning about a whole new database system too.