I attended to the shop because my laptop did not t...

I attended to the shop because my laptop did not turn on. The shop assistant diagnosed that the Hard Drive Disk need to be replaced. My informatic friend contacted to him for the HDD details to order and do it by himself. The assistant avoided to provide to us with it. With the intention me to buy to him. Till there all right. The scam was that he said the new HDD need to be ordered and replaced by them. My surprise was in three hours the laptop was ready. They did not order it because It is sold in the shop. They did not notice me that I could buy the HDD there and my informatic friend replaced it. So when I picked up the laptop I asked for my old HDD that was involved in the case of the new HDD with the price marked 170$. I paid 250$ in total for labour.
To summarize the scam was hiding to me and my friend that I could just buy the HDD and replace it from another side...