If you wanted to build another component that is on the scale of Word, Excel, Access, or Powerpoint, that will cost millions.
Those are very feature rich programs that take large teams of developers, project managers, testers, and more. People don't always understand everything that those programs can do and how easily they can actually work with one another.
For a real software project on this scale, $500K would be your budget for just getting the requirements and specification put together.