There is a configuration that can be done to a customer's network where all estimators can have access to the same project list and data at the same time. If you wanted to set up this configuration, you would need to purchase a Client/Server license that would control the multi-user environment that occurs when more than one computer is accessing the same data at once. If you didn't have this "client/server" license configuration in place, your eTakeoff's performance would slow down to a crawl because of how commands are exchanged and managed from such an environment.

Please click on the link below for instructions on installing and configuring the Client/Server license. 

eTakeoff Client/Server 12.0 documentation