Google tends to trust older domains over newer domains. I wouldn't worry so much about the IP of your site. Shared hosting is slightly risky in that you might share your IP with someone on a less scrupulous site. However it's best to get hosting in the country that you are targeting.
Google understands most websites are using shared hosting - they will not penalize you or lower your rankings if someone on your server is abusive. Google doesn't rank you based on other sites on your server, that's silly. The age of domain doesn't matter after about a year.
Domain & IP hosting doesn't affects SEO. It, may helps in SEO. I wish to share an article from SEO Explain which explains about various factors in domain & IP of SEO. Hope, it helps you better to get an exact idea.