For a quick education consider visiting:
www.ev-cpo.com. And
www.teslainventory.com
Cliff notes of what I detail below is (ignoring any potential federal tax rebate elimination)..
1.).if you are going to custom order do it this week or wait until January.
2.) If you want to buy an inventory car wait a few weeks for the end of quarter sales. Inventory may mean show room model, service loaner, but very frequently means brand new never driven cars.
1.) Why custom order now or wait unitl January you ask....or I ask for you?
Tesla does not negotiate. Tesla does offer private and public incentives based on how the quarters sales numbers are looking. Reduced loan rates, lease specials, waived delivery-destination fees, etc. These are sometimes publicly shared or in my instance I would get a call or an email with some type of personal offer...always near the last month of the quarter.
Because of these incentives the demand on the factory sky rockets at the end of every quarter. from assemblers to the delivery specialist everyone at Tesla works overtime the last month of each quarter....and the quality plummets. Whatever modest incentive you might get is not worth risking getting an end of quarter build. It seems like every time there are cars with issues they are end of quarter VINs.
Historically on the first day of each quarter Tesla announces it's upgrades/new quarterly pricing. This has been true every quarter except this past quarter (when they announced the upgrades early on July 23 to coincide with the Model 3 release).
They make the upgrade announcemebts on the first day of each quarter to not cannibalize the previous quarter sales.
2.) Why wait to order an inventory car in a couple of weeks?
Tesla builds a lot of cars to go unsold /directly to inventory. Then they put them on sale at the end of each quarter.
Recent examples.... In August they dropped the price of every 90/P90. These were undriven factory fresh cars being offered $8-$24K less then sticker. The reason they did this became clear when they dropped the prices of inventory 100's a few weeks later.
I have been privately offered to waive the $2,000 inventory delivery fee at the end of several quarters.
As others mentioned there was the infamous $7,500 discount on all 75's at the end of Q3 2016. Secretly the $7,500 discount was also available on 60s too but was only advertised on 75's.
If you go this route be patient and be ready to pounce when the offers do come up because they are only temporary. Tesla will be doing an interior upgrade in an upcoming quarter and you can be certain there will be a fire sale of inventory cars right before it happens.