Various towns in Marin do allow kennels and boarding services, sometimes the business are actually for sale - I happened to see one a couple of months ago.
The best place to find out about zoning for kennel or boarding animals is to talk to the cities you are interested in and the county (if the location is in the county proper). You can actually call the planning / zoning departments first before deciding if you want to go down and talk to them. The will also let you know about the process of gettng property permit and such.
Once you have decided the area to look at, then you can find the available property that's suitable for your purpose.
Then again, you can save all the troubles by talking to a Realtor who will be able to do the research for you and see if there are properties that are currently available for your purposes - not only for the boarding/kennel but also for the home, lot size, location, community you might be interested in within the price range you are looking for.
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