Expandable
There are many options available depending on the some of the factors that the other responder mentioned. I have actually been in this particular type of solutions for the past 15 years. I think the most important factor is choosing a solution that is expandable and configurable. Regulations and content format will always change. You do not want a solution that is outdated in a short period of usage.
Cost can vary from $90,000 to $600,000 to purchase a solution.
Hope this helps.