On the subject of only buying something once:
"There is hardly anything in this world which some man cannot make a little
worse and sell a little cheaper and the people who consider price alone are
this mans lawful prey, as it's unwise to pay too much, but it's worse to pay too little.
When you pay too much, you lose a little money, that's all. When you pay too little you sometimes lose everything, because the thing you bought is incapable of doing the thing it was bought to do. The common law of business balance prohibits paying a little & getting a lot - it can't be done. If you deal with the lowest bidder, it is well to add something for for the risk you run. And if you do that, you will have enough to pay for something better."
John Ruskin (1890)