Very nice site and I see you are using a wordpress SEO plug-in which is excellent. You are using good page titles and the site is (as most wordpress themes today are) mobile ready. You have a good amount of images, I would consider caching your pages. This can be done with your server/hosting.
Below are a couple of tools everyone can use to see how their site is and correct or share with their developer. Not everything is as important and the reality is that you are only competing with local sites that are in the same market when trying to get to the top of the list in searches, so fix what you see if its going to make a difference. I would type in keywords and phrases you think your customers would use to search for auto repair into Google, Bing, and Yahoo.
http://seositecheckup.com/ - search engine optimization test
https://search.google.com/search-console/mobile-friendly - Google mobile-friendly test, see if your website layout is mobile friendly
The web is changing and primarily because of new/improved coding languages and screen sizes. It is important to keep web site scripting up to date to minimize issues, hacking, and layout issues with modern web browsers. So this means updating the programs/scripts that run your sites or making sure your web developers keep them updated to the latest versions.
Google is giving more weight to mobile friendly pages because of phones and smaller screen sizes. When you look at your site, don't only look at it on your desktop or laptop, check your phones and tablets and see how it looks. Are you happy with it? Is it easy to navigate? Will your customers like it?
Lastly, are you running any analytics on your site? Ask your developer to add in Google Analytics, its free. You can get great insight to how your website is found, what pages are frequented, and other useful info such as ranking, demographics, etc.