Can you provide more information first? I wouldn't bid on this project without more detailed information. For example:
How does the data get into the system? By import, or by user interface, or both? Once in the system, does the data need to be edited? Is this part of the project?
What is the general structure of the data? A flat table, or are there interrelated records?
Are there different types of users that can do different things, such as import data, or view reports?
How do the 250 users get into the system? Is the developer responsible for setting those accounts up?
Comments
More info needed
Can you provide more information first? I wouldn't bid on this project without more detailed information. For example:
Thanks!
http://www.trailheadinteractive.com