The parts might only cost £20 but not everyone is comfortable repairing their own device.
So off you pop to the local repair man who tells you to have a look will cost x. Then the problem is found and its x. So you are standing in the store with the dilemma, pay £120 for a repair or a fully working second hand machine. Then another problem so you say screw it, and buy the second hand.
That's how you can quiet easily end up with constant replacements.
Someone said oh but work places don't use
Mac. Erm, surprised no one has mentioned this, you can partition a Mac and have the best of both worlds and run both os.
Someone said oh an external hd will be around £70 fuck knows how much it will be for the Mac. It's the same price. Most hd can be used on either os.
But op keep looking. That one isn't that great. Read reviews. Have a look on the dell site they often do deals and have refurbished ones.
Have a look on laptops direct
Have a look on trusted reviews and tech radar.
Office vs macs stuff. Office can be run on the Mac. You also have free stuff from open office. The Mac stuff personally I don't like. I get frustrated with it because it doesn't alley let me do what I want. But then I know others who prefer it. So for this stuff I would really say go pc world and have a play of office and the Mac version.
Apple care same with any other warranty depends on what insurance you have.