Hi there!
I understand you need an application for you and your customers, a kind of app like the frontend and backend of a CMS site where you can configure all you need for your customers, who can access and get the information you've configurated previously (prices, items, etc...).
I'm a 8 years experienced C++(RAD and Builder) and SQL programmer, so I can develope a Desktop application, but I think what you need is a web where customers can connect and see your prices catalog. It can be done in both ways, so you can decide what you need, a desktop app or a website online.
Anyway, first at all we take care of the backend (your configuration tools), and once it runs, then we begin with the frontend for your customers. You could see the progress at any moment so you'll be free to contact me for it.
I'm ready for you.
Best regards.