Backlinks and local visability

So we are a small car rental company in Bavaria. We started 6 months ago and we read something about SEO and how to do it. Since we can't spend too much on marketing, the idea was to "find" some backlinks. But this is so not successful. Contacting other websites is a very long process which I have the feeling leads to nothing in 99% of the cases. Do you have any helpful tips? I mean it doesn't need to be backlinks, we just want a good local visability.