Desktop Database Client Server App

I want a small desktop client server application for a logistics services shop. The shop receives input using a form for about 5 different services (aviation, vehicle, accommodation etc). Each of these services processing units have at least 2 individuals. I want a system that will be used to capture the inputs, this information will now be accessed easily by the processing team for further processing. The system will keep historical data, run series of reports indicating daily,weekly and monthly KPI reports Note of warning, 1. These personnel are all not IT literate so the system needs to be as simple as possible. 2. Up to about 500 forms received daily. Reports format to be easily adjustable. Limitation:Client only has LAN and no internet con.