So basically the best way to stay environmentally friendly is to maintain and service your car as long as you possibly can, until it really is beyond repair , the amount of cars I have seen scrapped that had a good few years left in them is astounding , I am currently doing up a 2005 Corolla 1.4 vvti , all that was wrong with it was horn never worked - Cleaned connection , replaced a rusty wishbone, couple of tyres , some brake pipes replaced , quite a few but actually a doddle when you have the correct tools, front discs and pads , cleaned up rear brakes and replaced a brake backing plate, wipers and hey presto an mot'd corolla in good nic with only 78k on the clock.
Paid 100 for the car , spent about 300-350, have a buyer lined up for 900,