NEW YORK, July 6 (Reuters Breakingviews) - Nextdoor is trying to keep up with Joneses. The neighborhood social network is merging with a blank-check firm sponsored by Khosla Ventures in a deal that values it at $4.3 billion. What Nextdoor is trying to build – an online community that unites, helps and enhances the places where its users live – is admirable. It’s also, sadly, vulnerable to being bulldozed by Facebook (FB.O). Founded in 2011, the company led by former Square (SQ.N) executive Sarah Friar aims to be a hub for information about yard sales, missing pets, restaurant hot spots and crime. In the United States, about one out of every three households turn to the site and it counts 60 million verified users around the world, just under half of whom visit once a week. Nextdoor has also managed to lure some big financial names into its neck of the woods, including fund manager T. Rowe Price and Silicon Valley investor Bill Gurley. Special purpose acquisition companies like Khosla Ventures have injected capital into many oddball ideas and products that don’t even exist yet. Nextdoor, though, has the opposite problem. Facebook is richer, more popular and is already targeting Nextdoor dwellers. In May, Mark Zuckerberg’s firm rolled out “Neighborhoods,” designed to help people connect with folks nearby. Facebook may not have originality on its side, but it does have an annual sales and marketing budget of around $10 billion. The competition extends to Nextdoor’s revenue-providers. Roughly 55% to 65% of Facebook’s $84 billion in advertising revenue comes from small businesses, reckons Pivotal Research. True, Nextdoor is growing faster. Its top line increased 49% in 2020 compared to 2019. But it is from a much smaller base and the company remains unprofitable, which makes its putative enterprise value of 20 times next year’s forecast sales – more than twice the multiple Zuckerberg’s firm sports – look rich. Friar’s firm is trying to position itself in contrast to the toxic content hosted by Facebook, Twitter and other mega-networks – even taking the stock ticker “KIND.” But kindness may not help it in the end. If lawmakers enact curbs on tech firms’ ability to escape liability for what their users post, it’s smaller companies like Nextdoor, with less to spend on policing their users, that could find their existence threatened. The rewards for being a good neighbor have never looked so uncertain. Follow @jennifersaba on Twitter CONTEXT NEWS - Nextdoor said on July 6 it agreed to merge with a special purpose acquisition company sponsored by Khosla Ventures in a deal valued at $4.3 billion. The transaction includes a $270 million “private investment in public equity” element backed by funds managed by T. Rowe Price, Baron Capital and Dragoneer among others. Nextdoor Chief Executive Sarah Friar also participated in the PIPE financing. - Nextdoor, a neighborhood social network founded in 2011, reported revenue last year of $123 million. It lost $75 million in 2020.