Imagine walking into a department store to buy a TV. You weigh up all the possible options and decide which model you want. The price of this TV is 457GBP. The assistant says ‘That will be 457 pounds, Sir’ as she takes the credit card payment and arranges delivery for next week.

You then happen to go up to the second floor and see the identical TV for 422GBP. That’s 35GBP cheaper than what you’ve just paid. You go back to the assistant who sold you the goods to query this difference in the price. Unfortunately, the assistant is now on her lunch break but you are promised that she will call you back. She doesn’t.

You then leave the department store via the ground floor where you see the identical TV priced at 565GBP.

You arrive home and just happen to check the credit card receipt. The amount debited is 476GBP instead of 457GBP. Silly you; you should have checked the amount more carefully at the time. You call the department store to complain. The customer services manager you need to speak to is on a break but he will call you back immediately. He doesn’t.

Well that is how online shopping for a Dell computer works. There are many different possible ways to configure the identical specification for a desktop PC and get a completely different price ranging from 422GBP to 565GBP. This difference appears to depend on which path (Offers page, Dimension page) you followed through the Dell web site (and which E-Code is listed) when you added and subtracted the various possible options to configure the final system.

So, if you are thinking of buying a computer from Dell, always compare every conceivable way of configuring the final system before placing the order. Always order on the Internet once you are confident you have obtained the cheapest price. Never order on the telephone from a human being. I was given one price on the telephone and when the invoice arrived via email, a higher price was listed.

Alternatively, it might be just simpler to buy your computer elsewhere.