Way to do this is to have a table of project codes where the key field is the project code and then make a relationship so that one project code has many purchase orders and project code as many budget lines.
Then you will be able to do a summary field on those two relationships to summarize the value of the budget lines and the value of the purchase orders.
------------------------------
Mark Shnier (YQC)
Quick Base Solution Provider
Your Quick Base Coach
http://QuickBaseCoach.commark.shnier@gmail.com
------------------------------