There is a big difference between loosing money because you build and sell individual cars at a loss, and investing in further capacity. They make money on the cars they build and sell, the overall loss comes from investing in the new factories and product lines. This should come as no surprise to anyone familiar with startups.
You're supposed to include capital expenses and depreciation in margins. Just because they're building factories doesn't mean they have higher margins.
This is why startups underestimate their expenses.
The new factory isn't part of the current production cars Cost of Goods Sold because it isn't being used yet. See the matching principle. The depreciation of the factory will absolutely factor into the COGS of the cars it produces in the future, but the increase in sales volume should compensate for that.
I wouldnt be surprised if Apple is working with Tesla for the model 3. They have the money to invest and help, I can see them owning 25% of Tesla for it. But the fact they are hiring away Tesla engineers argues against this point.
I dont think they have yet, but Im wondering if hiring Tesla engineers is a way to skirt that issue and help to collaborate/co-develop a product. I dont see Apple building it's own car from scratch, especially given Apples quality track record the last 5 years.