"Now is the best time to invest", no one can tell you that for sure. In fact, more people will argue that now is NOT than would argue that it is the best time. However, just as important as the home prices, interest rates, and etc is the question "Is now a good time for YOU to invest"? Please consider talking with a financial advisor, your CPA, and then a lender about investing in the market.
I do think now is a good time in general for primary residence, but as an investment not sure if we can say with 100% accuracy now is the absolute bottom. How diverse is your portfolio? There are many other questions and factors to consider. If you have the cash, Trustee Sale is a nice way to make the investment but it will need to be 100% cash, no financing. If not, please consider working with a local agent or Realtor to help you with your investment. Looks like there are a couple right here from the area that took the time to answer your question for you to choose from.
Please remember "now is the best time", no one should say that as no one can guarantee that statement.
Best of luck.