>I have a client that produces reports for their customers that change constantly and with little notice. This customer is interested in having us develope a package for him to produce these reports, but his concern is that we will not be able to produce these changes fast enough. Our answer for this problem is for the client to be able to set up and change the reports on the fly. Thus, I am looking for products that will allow this to be done. The report changes would involve adding and deleting variables, if this matters at all. Of course, the client wants to spend as little as possible...

Have you looked into Foxfire and Crystal reports? Do these meet your needs?