I agree with Franco. I've been making things for 40 years or so and I doubt that I have ever made something that saved me money by the time I got the final product. If an existing product is available I buy it. It is probably both better made and cheaper than one that I would make. And duplicating an existing product at home gives me no pleasure.
I only make things when I have a design for something that isn't available commercially. Even then my first choice is to buy an existing product and modify it to my liking if I can.