There's a plethora of articles, tips, and techniques about automotive SEO that fill blogs, webinars, and training courses. Everyone has opinions about what works best and how to help dealers rank better in search. The biggest mistake that dealers (and their vendors) often make isn't in the SEO techniques themselves but rather in the underlying keyword principles. It doesn't matter how good the SEO techniques are; if you don't have the right keywords selected from the start and make adjustments to the targets on a regular basis, your optimization is not optimal.
Here are some quick best practices to keep your keywords from going stagnant:
When You Hit Your Goals, Move On - This is the most common keyword mistake in the automotive industry. I see dealers and their vendors pushing hard for keywords that they're already dominating. They likely selected them from the beginning as high priority but never adjusted when they reached the top. If you're ranked #1 for a keyword, no measure of additional SEO effort will get you ranked higher. Stop. Move your efforts to other keywords. Monitor it - if you fall from the top spot, re-engage with that keyword, but otherwise point your attentions to getting more keywords.
Remember the Variations - So, you're going after a keyword like "Shreveport Honda Dealer". That's great, but what about the others? Order of the words matter. Plural variations matter. Synonyms matter. You should be going after "Honda Dealer Shreveport", "Shreveport Honda Dealership", "Honda Dealers Shreveport LA", etc.
Rightsize Efforts Based on Competition Levels - You don't need a rocket launcher to take down a rabbit. Likewise, a BB gun isn't going to take down an elephant. Apply the right measure of SEO pressure on your selected keywords - no more, no less. As a general rule, the more words that are in the keyword phrase, the easier it is to get. For example, "Minneapolis Toyota" takes a lot of effort while "2013 Toyota Camry Minneapolis" takes less. Also, the competition level in a given metro makes a difference. Keywords for "Los Angeles CA" are easier than keywords for "Thousand Oaks CA".
Go for Top 5 for Some Keywords - There are certain keywords where the effort to get to #1 simply isn't worth it. This is particularly true for keywords in cities where there is already a local dealership. If you're in Palo Alto and you want to rank for keywords in San Jose, the chances of beating actual San Jose dealers is low, but getting into the top 5 is usually achievable. Set your expectations properly and focus on getting more keywords rather than moving up a little higher for competitive keywords.
These are just a handful of best practices, but the underlying lesson is clear. Watch your keywords. Adjust them. You or your vendor should be adjusting your SEO monthly based upon where you rank for your keywords. If you let your keywords go stagnant, you're just spinning your wheels.