That assumes that you can sell the house for more than what you bought it at.
You are correct that principle may be recouped and in addition, you get a mortgage interest tax deduction. However, you also pay 6% when you sell the place and maintenance costs (~1% per year) need to be accounted for.
There are several assumptions you need to make for owning to be cheaper than renting - that usually involves owning for a longer period of time (>5 years) and some modest appreciation (~3%+).
Of course, my numbers were from the SF market. There are many cities in the US where owning is cheaper than renting from day 1. SF just isn't one of those.
A good place to mention the NYTimes rent versus buy calculator: https://www.nytimes.com/interactive/2014/upshot/buy-rent-cal...
Not necessarily; as long as the value of the house[1] doesn’t fall more than the principal you’ve paid, you’ll get more cash from the sale than you put up as a down payment. The trouble with buying on margin, though, is that it amplifies losses— the worst single day in the stock market[2] was about a 20% drop, but you get the same effect from a 1% drop in your house value if you hold the 95% mortgage that you described.
[1] Folding transaction fees into the effective value
[2] https://en.m.wikipedia.org/wiki/Black_Monday_(1987)
Also, once you hit 20% ownership, you no longer have to pay mortgage insurance.
I haven’t run the numbers lately to figure out which side wins, but the analysis is significantly more complicated than comparing monthly outlays in the first year.