Although I do not practice law in California, I assume California does not prohibit a relative power of attorney from receiving payment for services.  Florida law expressly authorizes such payment but does not prescribe the amount.  Professional fiduciaries (people who serve as guardians & representatives for a living) often charge $60 - $120 per hour or more for their services.  When preparing contracts for family members to serve in this capacity, Florida lawyers often allocate approximately $45 per hour for services.  You can also call some geriatric care managers in your area to find out what they charge and then charge your father a similar rate for similar services.  You can also call an Elder law attorney in your area to ask if there is any prohibition against a son charging his father for these services.