Hello:
I have been working with Microsoft Access (with VBA) since 1997. I have already been SQL Server DBA for 3 years
Actually, a part of my job is being a consultant for developers and advanced users on problems that have eluded resolutions by others
Regarding your job, I have a really huge experience. I wouldnt do it as simple as 1 table for customers and another for invoices... I would create these tables:
Customers
Agreements
AgreementsLines
Invoices
InvoicesLines (I think its necessary to complete word document 2)
Technicians
Besides, we can use these word documents as templates, so you can create these word docs. for agreements and invoices
I think that a fair budget could be about 210$, with Input forms for Customers, Technicians, Agreements, Agreements lines, Invoices and Invoices lines, and extraction to Word documents
Waiting for your comments
Regards