I'm not very good at computing and don't really understand how IP works. But I know Google doesn't like links from the same IP addresses. What if I get VPS hosting and get a unique IP address for every websites. Will google consider those websites as being on different IP addresses, even though all the websites have the same nameserver? Thanks for your help.
Your VPS won't help much since they are still under the same class C ip anyway, even each of them has different IP already. I would recommend not trying to game over Google with easily identical pattern. If you do really want to link across your own websites, I would recommend you hosted each website under different class C or B ip instead of just a different IP.
If your sites are pretty much in the same niche why don't you make a major site with subdomains, interlinking them is pretty much valuable than interlinking different sites with the same IP..
You should be able to get separate class c IP addresses on the same VPS. Google "seo hosting" and you'll see at least one company which offers this. I haven't used any of these companies myself so I'm not going to put a direct link in to any I found as I can't recommend any particular one. With regards to link building, yes I think it is important to get links from different class c IP addresses, so finding a host that offers this is a good way to get round the problem of having too many links from the same class c IP address. Also found this thread which may be of some help and also this blog post. You might wish to consider buying some cheap hosting plan from a variety of hosting providers and putting one site up on each instead of just having one VPS for all your sites, since it may work out cheaper, especially if you don't plan on having a large amount of traffic to each site.
My main concern is not interlinking websites but would I be able to rank two websites on my VPS hosting for the same keyword?
Links from sites on the same IP are fine unless the sites linking to you are not interlinked with each other. If they are interlinked, the may not give you much SEO value.
IMO, no. G has too many ways to know for certain that both belong to you. My guess is that ultimately G will treat one like an inner page. If the KWs are competitive, the second site (inner page) probably appears on page 2 or 3.
I think google doesn't care a lot, since most websites run within the same IP (like shared hosting); also private IP is expensive (I think $25/year)
Why do you say that? u have any information to say this? I would like to know more this becouse this is my situation lots of page with the same host