King Charles III’s heir — he’s also now his landlord.The 40-year-old Prince of Wales will be earning about $785,800 in rent from his father, thanks to a home he’s inherited in Cornwall that has long been one of the new monarch’s favorite places to stay, The Sun reported. Wills got the property, which is part of the Duchy of Cornwall’s $387 million portfolio, when the 73-year-old Charles ascended to the throne upon the Sept.