Have you toured the area already and that is how you focused your search down to the Northgate neighborhood? A lot of the homes that are currently on the market in Walnut Creek that are vacant, are REOs or short sales listings. I know that REO listings will not do leases or lease options, as the banks are looking to move their inventory. And I personally, do not recommend doing a lease on any short sale properties as there are no guarantees that you will be able to reside in the property once it falls into foreclosure.
There are twenty one active listings in the Northgate area currently, of which ten are vacant. Five of of those ten are non REO or short sale listings. None of them are offering lease options right now. There is only one advertised property on the market that is offering a lease option, but that property is located in Lafayette (and depending on your price point, it may be too much).
I hope that answers your question. If you are not working with an agent already, I am happy to send you active lease listings in the area and work with you to help you and your family find the right place. I have helped other relos in your same situation, and understand how stressful it can be moving from one state to another in a short period of time.
Well, Happy New Year and best of luck,