I've had my room fumagated for the second time, this time there appears to be no trace of them. But they seem to be hard to get rid of, do you have any advice for me please.
Bedbugs are a very rare occurence in California.
Typically if you clean regularly the bugs will not persist. They may hide during the day in linens and under mattress covers. Perhaps changing your mattress, and regularly cleaning your new linens will help. Additionally, clean any areas around the bed where they may be able to hide, and make a habit of cleaning those potential hiding places regularly. A sign of continued infestation will be dark stains on the sheets, caused by their excretions.