I will tell you, where it is possible to buy laptops at a bargain (especially, ones with 17 inch screen). In the UK there are a few main electronics retailers, such as Dixons, PC World, Currys, etc. They have special pages online, where they are selling refurbished laptops. Here is a link to the Dixons online refurbished laptops’ store. From my own experience, I could tell, that buying a refurbished laptop is a good choice.  For instance, I bought the Toshiba laptop with 17 inch screen and it keeps running perfectly until this day. The same is with Vista.  It is possible to filter displayed items there. For example, if I would like a laptop with 17 inch screen, I could screen size 17 inch on the left corner.
Another suggestion is to visit these sites frequently because they are selling-out very fast. I can tell from my experience that the availability of a laptop there changes every day.
Another great source of refurbished laptops is eBay. Sellers usually describe every item, whether it is used, refurbished or new on the eBay. Refurbished laptops there are be used there, but some parts are replaced to satisfy current needs of the customer. For example, we can find used MacBook laptops with 500 GB hard drives and 3 GB of RAM there. It indicates that seller has added more memory to the laptop and replaced its hard drive with the bigger one. Sometimes the casing part on the laptop might even be replaced. As for Macs, the palm rest plastic parts get broken and their replacement increases the value of the laptop. It is called laptop upgrades.

Laptop PC and Mac upgrades in London. Please contact us by phone or by asking a question online.
We also sell refurbished laptops and are able to configure any laptop according to your needs. We can upgrade any laptop including Apple MacBook and MacBook Pro as well. Please ask us questions. We try to provide answers in 24 hours. The question will be seen by other our site visitors, so you may get the answer very fast.