You can contact a California property lawyer to help you with this. You can find them by an internet search: "California property/real estate/eviction lawyer/attorney" or you can do this yourself. It sounds like since you hold the mortgage, this situation is similar to a contract
for deed. You would go through the eviction process to evict the tenants and regain the property. Your contract should have had language placed in it for the event of an eviction. If it does not you follow the laws for eviction in California. Here is some information: http://www.expressevictions.com/eviction-law-in-california.php
However, because they are landowners currently, this is not as simple a procedure as a regular eviction because they are not merely tenants, they are landowners under the contract. The procedure is more complex, and you may need legal counsel, but the site that I provided and others will provide some general principles to follow. A property lawyer may be necessary since they do have more legal rights than a pure tenant has.
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