I ordered the "default" Model 3 (SR+, white, 18" aero wheels) online October 4th after going to a Tesla Store and sitting in the driver's seat of a display Model 3. (I had ridden in one twice, briefly.) Was not prepared to be as taken with the cockpit experience as I was. It felt serene. More ergonomic than my other cars. I never felt remotely serene when trying to buy a car at a dealership. Awful--stupid games and long waits to wear one down. A totally untrustworthy experience. A Tesla employee answered my questions. After I said I definitely intended to buy one, we exchanged emails. I was to send my RN when I got it.
I was told to order right away for the then advertised two-week delivery date because resources were being directed to the opening of Shanghai factory. I ordered that evening. Was given some directions as far as completing the order as much as I could without showing my driver's license, insurance cars, title for trade in. With the scanned documents, an Order Agreement was completed for me. The trade-in value is shown on the Order Agreement. I doubt it will change. Seems we have some sort of contract. The price was subsequently raised by $500, and the range increased by 10 miles. I assume that by waiting, I will get a more "current" version of the car at the price I agreed to when I ordered the car, but the agreement is not the final contract.
On the plus side, with more manufacturing experience, the car's build only gets better. Tesla learns and tweaks.
My concern was not getting the car by the end of the year and thus losing the Federal tax credit. I checked with my contact at the Store and was told that the delivery times had changed for everyone. I would receive delivery of my car December 15 - 30th. I live near Fremont, but should get it earlier in the range because I was in the queue earlier. This evening I received an invitation to an Owner's Workshop. I am asked to bring Driver's License, Insurance card, and for a trade-in vehicle--the title and current registration card. Tesla advisors will help me complete my Tesla Account and be prepared for my delivery appointment. So attending this gathering is a way to expedite the delivery process. I've had six weeks to learn about the car, order/receive items from the Tesla Store, learn about Sentry Mode and format my USB device (simple), watch a lot of videos, read the owner's manual. I've read that often the planning and anticipation of a vacation surpass the actual vacation, but I'm expecting the Model 3 to be more than worth the wait.