This is my test for a dealer, if they're difficult over email things aren't going to get any better in person. I'll only negotiate a deal over email moving forward...everyone I've done has resulted in smooth and pleasant transactions.
This.
I've been doing this for years. Used to do it via phone before email became the standard.
You find out real quick the people who value customer service and the people who are just going to try to roll over you.
Even those dealerships that facilitate electronic communication, about 30% of them still want a phone #, and they won't hesitate to use it.
I found this out straight off. they would respond via computer, then want to use the phone to further work people.
I had several try this, even after saying in the email that all communication is to be done electronically, and that phone calls will not be accepted.
This last time, I was working with a dealership in Indiana and was about ready to pull the trigger when the salesperson for no apparent reason went gnarly and got a case of red rump. The beauty of this strategy was that I did not have to find a way to extricate myself from the dealership, all I had to do was electronically disengage. Which, I did.
The beauty of this method is that it allows one to expand their horizons, price a larger # of sellers than would be physically possible, find the best price, and have it confirmed in writing.