Ideally, at least three years. More is better, but are they up to date with new technologies?. Prime Soft Technology advises: Obviously, a company that has been in business longer is likely to be more stable than a new start-up. The first three years of any business are the toughest, so look more carefully at companies younger than this. However, there are disadvantages to older businesses, particularly in technology, as they might not be up to date.