Ask HN: Good business administration software / workflows

I'm working at a small consulting firm (15 FTE) run by students parallel to our studies. We're looking for some kind of business administration software that can be used to keep track of ongoing projects. See who is working on what project, perhaps generating invoices, keeping track of what projects we have done for a certain customer etc. Like a database with that contains our consultants, the projects and the customers (with a lot of fluffy things around it of course). Currently we're keeping track of everything in excel spread sheets, which kind of work, but is a ugly solution. Invoice are generated manually by one of us etc. I haven't found anything good yet, and before I dive in and try to write something custom, I'm wondering if HN has any solid advice. Thanks.