Check rent's on Craig's list or contact a professional property manager with Cal Narpm, they can assist you in the decision analysis.
If you do buy the condo, make sure you get the correct insurance, H06 landlord policy that will protect you for loss of income and rents, liability and wrongful eviction.
You would get positive cash flow from a condo investment in this area. It will provide decent return on your money, however, I've seen better areas to invest in that provide better return on your money and are in similar type areas.
We checked out Clayton a few weeks ago:
We lived in Dublin for many years, and we are looking to move back up there.
We were very impressed with Clayton; small town flavor, but close to everything.
I think it would be next best to Walnut Creek.
Good luck and may God bless