Heat maps are great, but automotive platform providers need to do their own usability studies with UX experts (in-house) and prove that to dealers. If an interface (VDP, Home Page, Showroom, etc.) is built poorly, there is no heat map in the world that is going to make a difference.
Somehow, I find this missing with most platforms. Dealers just say, "well, ok thanks for the website."
I love when people show me a terrible UX with a heat map on top to show that users are able to use it.
The heatmap doesn't show dropoff, confusion, frustration, etc. It only works for the people that already got that far.
1. make sure they're getting there successfully
2. make sure they're not spending too much time before their first interaction, that indicates confusion
3. make sure scrolling is tracked, especially how many times they go up/down/up/down
4. track clicks on photos carefully - there's alot of data there if you can track how many photos deep they go, etc
There's never too much information you can collect, but I would give very little value to heatmaps unless you are specifically A/B testing 2 options. If you're a huge fan of going that route, look into one of the javascript solutions that "screen records" the visitor so you can see how long everything took, where they were drawn to, etc. Time between clicks/movement is as important as where they click each time.