Good decision. Depending on where you live in Canada, a consistent salary of $150k (it sounds like your wife doesn’t work?) isn’t really enough. If you’re in Toronto or Vancouver, $250k is good, but not really good enough to be spending that much on a car.
Good idea waiting for now. I’d say wait a couple of years to build your business, build up credit, and then you can buy a model S with a much smaller down payment (or none) and get a good interest rate. My rate that I got from Tesla was below prime and I out down a down payment that I was comfortable with without taking any money from my investments.
And in regards to some of the comments and suggestions from others on here, the used car market in Canada is very different from the states, as there isn’t as many to choose from and they are often very low mileage as we have to drive a lot less, so the prices stay a lot higher for a couple years used (ie no used Model S’ available does $50-60k. They’re still usually in the $80k+ range).