Generally speaking, while working in a small company (30 to 40 employees) that doesn't have a policy for raises, how often should I negotiate one?
If this is relevant, I'm a software developer in Europe.
More specifically, here is my situation: I got a new job 22 months ago and was bad at negotiating my salary (partly because I started working in another country where the market was different but most of all because I'm just bad at negotiating a salary).
9 months after that, I asked for a company car and compensation for fuel. I had an ~18% raise (which is not that bad I think).
However, after after a few discussions with colleagues and other people working in the same field as me, and after seeing job offers, I realize I'm still underpaid. I think that if I had another 15 to 20% raise, I would be paid fairly (not too bad, but really not overpaid either) according to the market.
The thing is that I think I could just work somewhere else and get a 20% raise easily. However, apart from my salary, everything about my job is great and if I change, I'm 90% sure I would get something that's not as good. So, I'd like to negotiate a raise with my current employer but is it too soon considering that I have not been here for 2 years and already had a nice raise once?
What could I lose asking too soon?