Topic: Help! Network audit and software i could use

Need help at monitoring our network. My boss didn't tell us about his requirements when our IT department (consisting of two people, including me) was building the network and haven't had any issues with that. But a week ago he decided to take a look at hardware and software, which is installed on PCs with inventory numbers, etc. We have a pretty small network with two servers and 50 nodes but it`s too much to handle using your own hands. I've tried Spiceworks and it was too slow at scanning. With Total Network Inventory software audit tool I managed to scan network but had to take a look at some software like Autodesk manually. Any tips here for future? I need a tool (or tools) to check network automatically. Freeware, if possible.