The BBB is the best backlink money can buy. A plumber I met said it paid for itself in the 1st week. All government backlinks are gold, for example if your State makes your dba information available online. For local SEO, what ranks highest are those links that indicates a business's "legitimacy".
Think about it. Google is trying to deliver real-time information to real people at the moment they need something, for example a locksmith. Or an electrician. The first rule of winning (for Google) is to NOT LOSE. Meaning that, Google is concerned first and foremost with NOT giving their customer the Name, Address and Phone Number of a business that does not even exist. So anything that indicates permanency (like a government record, etc...) is going to give a business a significant boost over those that never filed a dba, or whatever other government documents you might be thinking about. Example articles of incorporation, or LLC filing. In Texas, the State makes this information public, and they have a spot there in the record for the URL of the business's website, as well as the Name, Address and Phone Number (NAP) and other factors. When Google sees one or more government records matching with a BBB record, matching Facebook, matching Twitter, matching Pinterest, matching the data on the website, matching a Google Local Listing (whatever it's called now), matching X, matching Y, matching Z, etc... (get the idea yet), that business is REAL and is going to rank higher than business that do not have the depth and breadth of a consistent NAP.
It's all relative within the niche. Plumbers aren't competing with Dentists. If you are the only Dentist with a public LLC and a BBB listing in town, you are going to rank higher than everyone else, no matter how much money the competition squanders on spam backlinks to fake twitter accounts. It's all relative, but some factors are more important than others. All other things being equal, maybe a few thousand spam backlinks might make the difference between placing #5 instead of #6, but if your business is the only one in your niche that has a public LLC document on file at the .gov website, you're #1 no matter how many spam blackhat backlinks everyone else spends money on.
