I'm not sure where this conversation is at, but I do have an extremely strong opinion towards a DIY, non-vendor, and/or in-house solution. I was a website/developer that came into the automotive industry with ZERO automotive systems knowledge. I had 60-days to bring our family of websites for our group in-house and away from a vendor. I didn't know what a DMS, an inventory management system, what a XML lead, how an automotive CRM system worked, or what a inventory feed was. Within those 60 days (actually 65, I rolled out 5 days late) I was able to design, develop the entire site front to back as a single person team. I received no help from any vendor (all were clueless on how to connect the pieces or didn't want to help), zero in-house, and zero external help.
That website has outperformed our vendor website by 3x total visitors, increased our organic traffic by 2.5x, and doubled the lead volume vs previous vendor site. All within 3 small to medium sized markets - combined market size of around 400,000 people. Our markets didn't magically double in size, I was able to exploit the weaknesses of vendor templated VLPs, VDPs, and websites to start the domination of market. Those weaknesses still exist today, although I see some vendors catching on. A good non-automotive website agency can easily find these same weaknesses and exploit them as well. It wouldn't take much for an outside agency to learn the systems and produce a very functional and well performing website.
The combined numbers (1 group site, 3 websites for each market, and 1 group mobile site)
Organic Traffic
7,275/month ave - prior vendor
17,304/month ave - current
Total Visitors
11,504/month ave - prior vendor
30,374/month ave - current