You just wake up to ask this question? Thought I was telling you about this issue so many times. The return is not as lucrative as you might think. You can get the answer from the table on detailed cost computation of owning a house that I have posted in this thread.
Edit:
A simple rule of thumb would be, so long…
the annualized appreciation of the house is greater than annualized return of the investment less cap rate
is worthwhile holding on to the house when house is fully paid or for full cash purchase of house.
Assuming the investment vehicle is S&P (historical annualized return of 7-11%),
For SV, cap rate is about 1%
Annualized appreciation of the house should be 7-11 less 1 = 6-10%.
Historical appreciation for houses in SFBA is 6-8% 
For Austin, cap rate is about 5%
Annualized appreciation of the house should be 7-11 less 5 = 2-6%.
Historical appreciation for houses in Austin is 2-3%
Guess market is fairly efficient. Always arbitraging 