I paraphrased (don't want to single them out here, in case) what a "Local SEO" company is saying in its marketing material. They "seem" to be doing reasonable amount of business based on their client references (who knows for sure without contacting the refs?) and show up on a ranking national Top List of SEO Companies (which can also be "bought"?). Seems to me that they are changing their PBN into a Public BN, no? Unless they have a massive network and are meticulously careful, are they risking their clients to a crash and burn? Or, do we not take them literally - perhaps they are creating a unique PBN for each client? Perhaps reduced, but still risky if G ever sniffs it out (and G only needs to read their website - and who knows what footprints they leave on client sites - e.g. "powered by...")? Also, if a client is not completely ignorant, or starts asking / searching around they'd find that there is risk to this approach. Maybe these guys are just "good" at SEO to get their company out there, and the rest is "fluff" - they're in for the quick buck vs long term anyway? Are their clients going to be ripe for the picking? Or, can a sustainable SEO business be had if "done right" and "done lightly"?