When it comes to his own clothes, Charles admitted he can't repair and maintain as much as he used to because of his changing shape.
He told Britain's Vogue magazine: "I'd rather have them maintained, even patched if necessary, than to abandon them.
"The difficulty is, as you get older, you tend to change shape, and it's not so easy to fit into the clothes."
One outfit the prince is willing to wear over and over again is the suit he wore for his son Prince Harry's wedding to Megan Markle.
Asked if he considered wearing something new to the wedding instead of the Anderson & Sheppard suit from 1984 which he donned, he said: "I've considered it. But in the case of that particular morning coat, as long as I can go on getting into it, I only wear it a few times a year, in the summer, so obviously you want to keep those sorts of things going.
"But if I can't fit into them, then I just have to have something new made. But I'm not sure quite how radically different they can be at my age."