Progress is a fine product. I suspect he vendor is trying to drum up business by intimating that NOBODY can mess with Progress but him.

Progress is ODBC compliant which means you can use Crystal Reports, and VB to mess around with it. You can also link Access to the tables in a Progress db, and do all sorts of things. Progress also has internal reporting facilities and dml (data manipulating language), plus SQL. It's a truly GOOD product.

There is however, something decidedly not right.

It doesn't sound like whoever did your software search did a thorough job. At all. The product at the top of the list only meets 85% of requirements. This is absurd. I was just at a CIS conference in Albuquerque. There are HUNDREDS of vendors that have
already written for Billing, Inventory, etc.
virtually anything you can consider, and at almost every price range and platform.

Your business model is not so unique that there aren't 10 products out there that match it 98%.

My professional opinion - redo the search. Correctly.
This kind of thing derails a companies bigtime, and any CEO who puts up with it is letting himself into a quagmire.