I have found a SEO which maintains sites related to hotels in main cities in Europe. This SEO placed about 8 links to my site and I respectively to SEO's 8 domains.
All of these 8 sites have different domains and link pages with PR 4-5. The thing is that they all have the same IP address. In addition to 8 they are offering more links from other domains, but again with the same IP address.
How google will consider these links? Do I risk of getting PR0 from this?
I wouldn't worry about it too much. As long as your site is relevant to the searches that it comes up for. I have found dozens of sites with the same characteristics in a few very competitive categories. I would only worry about it if you are misdirecting visitors. I suspect if the practice becomes a threat to the "purity" of PageRank, then Google will start filtering the sites on the same class C block. But not yet, as far as I can see.