Construction work-flow database

We are a subcontracting company, wanting a simple intuitive database system. We require easy invoice generetion and the ability to quote work. Basically a form query based database for eg, 12meters of joint sealing at $12.75 per metre, with the ability to show outgoing cost to us and chargeable costs to clients. We use maybe 30 materials. Thanks Please see attached file for full scope of project.