Depending on how long you intend to use the site for will influence how much effort/money you spend on it. Ranking doesn't usually happen overnight so you'll have to spend some time waiting either way. Aside from the usual advice of having original quality content you might try on page adjustments to start as the first on your 'SEO checklist'.
That means: images with real file names and alt tags, links to social media in the header and footer, a cached website, minified javascript + HTML and a sitemap at the very least.
After the actual website has a google page speed score of 80+ and a first load time under 3 seconds you're in a grear position to start building backlinks to a site meant to last. Don't just point shitty links straight at the site, make sure that anything pointing at the moneysite has a low spam score, preferably 0 and is at least somehow slightly relevant to the clients industry.
You can gain a substantial amount of traffic by leaving good relevant answers on sites like Quora with a link to the site in your answer.
If it's in retail then submit some coupons to voucher websites, submit the site to business directories. Make a company profile on local business sites.
You can also reach out to blogs with good metrics in your clients industry and at least leave pertinent comments with your URL but better yet reach out to them about contributing to a post.
Use different anchors for your backlinks, don't have 100 websites that all link to your site with the word 'keyword'. It's obviously fake, use longtail keywords like '2017s best keywords' or 'keywords that help you rank without being a jacka$$'. It seems simple but a lot of people forget the importance of varied anchors and sources.
In terms of using PBNs and services like press releases and social signals, there is already a ton of info on the forum. Just remember you're not going to buy the 'Spiderman's exclusive big D PBN' and rank for a keyword like 'insurance'. Realistically ou want a KW difficulty of less than 40 for a site you hope to rank soon, but when you're working whitehat the best thing you can do is build a site worth visiting.
Hope it goes well!
