I do computer repairs as a hobby, I do get paid quite decent , it takes me about 1hour to repair hinches on a laptop and have it all back ready with-in 1hour, around 25pound I accept for that, that includes my labour and purchase for new hinches, their cheap on ebay, I think this is the cheap way to doing things, buy on ebay, repair computers and get paid.. just promote yourself with business cards, I don't personally think theirs alot in it but it's a nice little hobbie to earn a extra penny or two.
I learnt personally by just building a computer, I was 14, ever since I've gone from computers to laptops , laptops are way different from computer builds, and requires alot more patience and a good sense of knowledge, laptops are very tacky but it's better for you to know more about laptops since the new age is laptops, everyone has one now, not a system...