If you no longer have mental capacity and have not signed and registered an LPA, then it would be necessary for your family to apply to the Court of Protection for a deputy to be appointed to deal with your financial affairs.
Before you become a deputy: The application fee for a deputyship order is £371. If you are applying to become both types of deputy, you must pay double the amount. If the court decides a hearing is needed, you must pay another £494 per person applying for deputyship. There are also ongoing yearly fees that now fall to the hardship of your family to cover.
Setting up your LPA now saves money and stress for the future and secures the attorneys of your choice, not one appointed by the courts to whom you cannot communicate and express your wants and wishes.