I have a 5 month old site that use's Amazon Affiliate links and Adsense ads for revenue. The main 3 keywords have 40500, 22200 and 8100 US searches per month and current rankings are 13, 11 and 15. There are other related keywords with lower search volumes in the top 10. The revenue so far is Jan $5, Feb $17, Mar $51, Apr $83, May $123 and June $57. Ideally I want to sell this site in 2 or 3 months time to fund a portfolio of sites. I have used a web 2.0 pbn with an average of 10 articles per web 2.0 blog, I do use social media and blog commenting too. Do I strengthen the current tier 1 with more tier 2 backlinks or create more web 2.0 blogs to improve ranking?